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The VPN won't see anymore than your ISP already is. So even if the VPN was logging everything you did, shouldn't it just leave you in status quo? How can it ever compromise your identity, that you move your "entry-point" from your ISP to a VPN?
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After buying a used computer from a stranger, what steps should be taken to ensure it is safe to use for connecting to a network that handles sensitive information? (I am defining "sensitive" broadly: notes to a loved one, corporate trade secrets, and the location of several of Russia's submarines.)
I am imagining that the system's components should be passively inspected and dealt with in a more active way. By "active" I mean, for instance, repeatedly erasing a mechanical storage device with the assumption that it contains some form of malware.
I am assuming that any used computer may have reparable security problems. The seller may not be aware of those problems. In more extreme cases, he or she may intentionally provide a compromised system.
A common, but of course not universal, situation arises when buying a system on eBay which previously ran Windows but will now be used for Linux.
In the event that a system's issues are actually too severe to repair, it would be nice to know that so that it can be avoided.
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Specifically, the problems with OCSP that Adam Langley talks about here?
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Some financial websites that I use use passwords in a peculiar way. Instead of asking me the whole password string, they only ask me to enter e.g. "3rd, 5th and 8th character of your password", i.e. a random combination of characters of the password string.
I think this would make sense if it's done using a shared random number table etc. But this is a password. In order to do this, they'd have to either store my password without hashing, or store the hashes for all the combinations they want to ask, which also sound bad. Am I right to think that this is a fairy bad security practice?
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I am using Bitdefender AV 2013 ed and I have noticed that when the Scan SSL is enabled in the configuration BD will use a local certificate, as mentioned here. This modifies the cert chain with BD as the trusted root on secured sites, or at least that's what you see. My questions are:
1) What is this kind of technology called?
2) What is actually taking place behind the scenes with cert validation?
3) Is BD masking the actual cert chain or does it actually substitute its own root for the site based on doing its own checks then tells the browser its "trusted"?
4) Is the presenting server involved in this process in any way or is it oblivious to what the client is doing?
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a friend challenged me to find out the ip from the new web server he uses.
Is there a rainbow table or something similar with all possible adresses or are 4 billion numbers to much for a normal consumer pc ?
Is there another way to find out the right ip ?
Is there any possibility to find it out if i know the webhoster where he is hosting ?
For anyone wondering the md5 hash is "f39d1e9bce27c0f31f536a272e544a16"
Greetings Tim
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the story looks like this: we have a browser, we have attached windbg to this browser,
we have a fuzzing 'page'. now, when browser will crash (and i.e. I know that bug occurs somewhere in the HTML code), how can I find that code which crashed the browser?
is there a way to find it during the windbg session?
appreciated for any help.
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I have a multi-factor web authentication server, that in addition to regular passwords uses fingerprints for user authentication.
Can anyone think of a security flaw in the following scenario:
I have Resource Server that hosts valuable resources, the resource owner must provide his fingerprint to an authentication server to grant access to his/her resources.
Securing the fingerprint data is critical. Before the user can use the system. He must install a web browser plugin. During the plugin installation the plugin connects to the authentication server and obtains a digital certificate from the server (a server public key).
Now when the user goes to the resource server webpage he types his username/password and the web page asks him to scan his fingerprint. Then, the web browser plugin connects to the fingerprint scanner and triggers the scanner to scan the user's fingerprint.
The plugin gets the fingerprint from the scanner and encrypts it using a randomly generated 256 AES key and then encrypts this AES using the authentication server public key.
Then the plugin returns a JSON object containing the encrypted fingerprint and the encrypted AES key. Next a Java script from the resource server login page using AJAX send the JSON object to the resource server. The resource server forwards the JSON object to the Authentication server.
The authentication server decrypts the AES key using its private key and then uses the recovered AES to decrypt the fingerprint data. Finally, it compares the received fingerprint data with the stored fingerprint template and returns the result to the resource server. Based on the result the resource server denies or grants access to the user.
The fingerprint templates on the authentication server are stored in an encrypted database using a 256 AES Key.
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Would you please tell me what is the difference between Anti-skimmer and Anti-fraud in ATMs?
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First of all sorry if I am asking a trivial question.
As far as I know, XML is used for representing document structures. Can entirely static sites accepting no user inputs at all be vulnerable to XML, DTD and entity attacks?
If it happens, In what context is it possible ?
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We build software which needs a SQL SERVER database. This database will hold private user information (address,bank, ...)
My question is: Should I install my database in a fresh SQL Server instance, or can I use an exiting instance?
(I doesn't want to wast user resources but also want to deny unauthorized access)
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I'm setting up a home HTTP server which can send and receive JSON data to/from different clients (Android and iPhone apps).
I'd like to allow access only to certain users and I'm considering using a simple username/password mechanism, as setting up client certificates seems a bit of an overkill for this small project.
Of course I can't send clear passwords from the client to the server on plain HTTP, otherwise anyone with wireshark/tcpdump installed could read it. So, I'm thinking about the following mechanism:
The HTTP server can be set up as HTTPS server
The server also has username/password database (passwords might be saved with bcrypt)
The client opens the HTTPS connection, it authenticates the server (so a server certificate is needed) and after exchanging the master key, the connection should be encrypted.
The client sends the username/password in clear to the server
The server runs bcrypt on the password and compares it with the one stored in the database
Is there any problem with this kind of configuration? The password should be safe since it's sent on an encrypted connection.
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What are the main components that JavaScript malware targets on the browsers ? Which aspects of browsers on which JavaScript takes advantage to exploit them ? And which techniques are used by malicious web content to attack browsers ?
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I am trying to understand how/if an email I received is being encrypted.
A financial institution sent me a verifiable email (i.e. not phising) asking me to fill out a pdf form to complete a transaction. The outbound email contained my account information and a completed pdf form in my reply would contain even more personal and banking information.
This email contained the words {secure message} in the subject and instructions to reply specifically to this email to ensure continued security. This message was sent to my gmail account and contained no PGP or S/MIME information. I have never set up any type of prior secure email configuration with this institution.
I replied to the sender expressing my concerns that this did not appear to be a secure means of communication. I was assured that the communication secure and used passwordless encryption provided by ZixCorp.
The company seems to offer 4 email security products:
ZixGateway
ZixAccess
ZixPort
ZixDirect
ZixPort pulls you to a secure portal to retrieve your message while ZixDirect prompts you for a password in your inbox, neither of which happened. The first two are only supposed to be for receivers with Zix email products. ZixGateway is just a public key-store the enforces rules compliance by chosing a best method of delivery including the above two options.
None of these seem to be describing the passwordless direct-to-inbox email my financial institutions claims is encrypted.
Does anyone know what could be going on? Is this type of encryption even possible?
Update 2014-08-05
Per makerofthings7's comment I checked the MX records for gmail.
$ nslookup -q=mx gmail.com
Server: 130.167.128.4
Address: 130.167.128.4#53
Non-authoritative answer:
gmail.com mail exchanger = 20 alt2.gmail-smtp-in.l.google.com.
gmail.com mail exchanger = 5 gmail-smtp-in.l.google.com.
gmail.com mail exchanger = 30 alt3.gmail-smtp-in.l.google.com.
gmail.com mail exchanger = 10 alt1.gmail-smtp-in.l.google.com.
gmail.com mail exchanger = 40 alt4.gmail-smtp-in.l.google.com.
Authoritative answers can be found from:
gmail.com nameserver = ns2.google.com.
gmail.com nameserver = ns4.google.com.
gmail.com nameserver = ns3.google.com.
gmail.com nameserver = ns1.google.com.
ns2.google.com internet address = 216.239.34.10
ns1.google.com internet address = 216.239.32.10
ns3.google.com internet address = 216.239.36.10
ns4.google.com internet address = 216.239.38.10
There is no listing for zixvpm. Any ideas why this might be?
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Does the EICAR antivirus test work on antivirus scanners for Linux? The EICAR test is described in more detail here:
http://en.wikipedia.org/wiki/EICAR_test_file
The reason I ask is that it requests the EICAR file to be a .COM file, which is specific to Microsoft as far as I am aware. Should Linux antivirus software still pick this up though since it is a standardized test?
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My coworker and I are developing an authoritative server for an MMO. We can't agree on how to handle "misbehaving" clients. Misbehaving, in this case, means clients who send "odd" requests that might indicate a compromised/altered client, or even a nefarious user injecting data directly into the communication stream.
One of us believes that the offending request should be aborted, the client's data saved, and the client's connection forcibly closed ("killed"). The other believes the request should be aborted and a "failed" response returned to the client.
We're at an impasse because we can't decide which approach is best. We've both generated arguments, but nothing has been sufficient to sway either of us.
For reference, here are some things we've considered:
Being disconnected results in an annoyance for legitimate users if we make a mistake coding the "misbehavior detection"
Killing the client eliminates the need for "clean up" response code.
If we don't kill the client, we might make a mistake and continue processing the bad request.
Killing the client prevents a compromised client from sending other potentially bad requests, at least until they log back in.
A disconnection may not do much to deter cheaters, whereas a denial response may elicit a "big brother is watching" feeling.
Any feedback on our arguments? Are there any other reasons for choosing one over the other? Is there some industry standard, or even a best practices consensus?
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According to National Public Radio, Ruben Santamarta has reported that gear aboard airliners and accessible through on-board WiFi or in-flight entertainment equipment uses hard-coded login credentials. http://www.npr.org/blogs/alltechconsidered/2014/08/04/337794061/hacker-says-he-can-break-into-airplane-systems-using-in-flight-wi-fi?ft=1&f=1001
I understand why hard-coded credentials are bad, but I also understand the airlines' problem: they have to service hundreds of airliners at dozens of locations. At a minimum, it seems like there should be a default password, changeable by the airlines, so that, e.g. Delta could have one system-wide credential and United another. That would also allow credentials to be changed after the inevitable leaks.
My question: Is there a better approach?
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I have a DD-WRT based wireless network with strong password security. However, other machines on the network may not be as protected as mine. If these machines are compromised, need I fear the attacker can more easily hack my machine, having gained access to another machine on the wireless network? We do not share domains.
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When using (Thunderbird and) GnuPG to send a PGP/MIME message to two separate recipients, with the text body different in both messages, but the same file attached to both of them, does this give an outside attacker that observes the traffic any additional advantage without knowledge of the plain text?
I realize that this allows attacker to guess I sent the same file (emails beyond a certain size can be guessed to contain attached files anyway). But what I am interested in is whether this gives an attacker a tangible advantage of any kind that could allow to retrieve the plain text?
Keys used are RSA, recipient key is 2k, mine is 4k.
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As per my understanding , openssl will verify the certificate of the server during ssl handshake , using the trusted CAs present in the CA certificate dir in the context. After the server certificate is verified and handshake is done , does the openssl cache/store the verified server certificate?
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I'm interested in using SaltStack in stand-alone minion mode as a way of automating the various configs that I want to do for my personal dev environment. But as a good security conscious dev, what kind of attack vectors would I be opening myself up to here? Or are there any?
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Sorry I'm not sure this would be the best place but I've noticed this icon recently. I'm not sure what it is and it only pops up sometimes. When it does, I can't click it or do anything to it and it disappears a few seconds later. I don't recognize the icon as anything I installed. If anyone recognizes this icon and what program it's for that would be great. I would just like some assurance that its not a virus or some kind of keylogger. Thanks.
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I need to send sensitive information from one piece of hardware to another. I was thinking wifi, but if someone obtains the password, it wouldn't be encrypted. I don't think you can use ssl unless it's a website, but I may be wrong. I don't know if it makes a difference, but it only needs to be one way.
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I've been reading about 2-way SSL or mutual auth recently, and here's what I've figured so far:
Mutual auth is a way for the client to authenticate itself to the server, just like the server does to client during (1-way) SSL connections. Web browsers are preloaded with the certs of well known CAs, so, when a website sends it's public key (something like a .cer file?) the browser can use the CA's certificate to figure if this received certificate is valid or not. Similarly, in 2 way SSL, the server needs to have the client's CA's certificate, or the self signed certificate using which the client's certificate was generated to confirm if the client is authentic or not.
Following are some specific questions about which I'm not yet clear and I'd appreciate if someone could verify my understanding:
The certificate that the server sends for 1 way SSL just contains the public key of the server right? Is this necessarily a .cer file, or something like a .cer file?
The CA certificates that the browsers come preloaded with - are they like .pfx certificates? And just having these certificates is enough for the browser to confirm if the cert received from the server is a valid one or not?
In case of self signed certs, does the server need to have the .pfx self signed certificate from which the client certificate was created?
I guess it's clear from my questions that I'm not even sure when the public key and when the private is key is used to encryption/decryption, so when you answer these questions, I'd appreciate it if you could also mention which keys are used for what purpose when a specific certificate is used.
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Assuming SSL/TLS cannot be used in this context, is this method secure enough to authenticate someone without someone listening to be able to retrieve the password from the information transmitted.
The client sends a login request.
The server replies with a unique identifier for the login
The user enters in the password
The client hashes the password and encrypts the identifier with the hashed password(encryption(value: identifier, key: hash(password)))
The client sends the encrypted identifier + the username
The server receives the encrypted message gets the decryption password from the database using the username the client provided and checks if its able to retrieve the identifier using the password.
If the identifier is successfully retrieved by the server authentication is successful.
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Below is an informal protocol narration of a simple authentication protocol. A sends to B a signed hash of message M, B's name and a nonce N. B knows that the message M is intended for him, that it originates from A and that it was sent as part of the same run.
A -> B: (M, A)
B -> A: N
A -> B: {| #(M,B,N) |}sA
But what will happen if we omit B's name?
A -> B: (M, A)
B -> A: N
A -> B: {| #(M,N) |}sA
I cannot think of a concrete scenario with a harmful attack. What attack could cause harm? A possible scenario is listed below:
A -> B: (M, A)
B -> A: N
A -> I: {| #(M,N) |}sA
I -> B: {| #(M,N) |}sA
There is no proof that the message was intended for B. So, intruder I can intercept the message signed by A and redirect it to B, authenticating I as A. But what is a harmful attack? For example in a bank-client interaction scenario?
Thank you.
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In ADFS, serveral certificates are used. This is explained (very clearly) on this page: http://blogs.technet.com/b/adfs/archive/2007/07/23/adfs-certificates-ssl-token-signing-and-client-authentication-certs.aspx
Now, I have configured the following:
ADFS Communications certificate
ADFS Token decrypting certificate (for tokens that are received from another FS)
ADFS Token signing certificate (to sign the tokens that are sent to the relying parties)
And on relying party level I have configured the following:
RP Token encryption certificate
Now, what I don't understand is how to configure the request verification certificate. In ADFS, you can find it in a tab next to 'Encryption', and the explanation is the following:
"Specify the signature verification certificates for requests from this relying party."
I assume I have to add a clientCertificate or something in the web config of my Relying Party, but I don't want ALL requests to be signed, only the requests that are travelling to ADFS should be signed. I want to do this because I do not want other, random apps to be able to contact my ADFS and consume resources.
Does anyone know how to set the request verification certificate?
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I am not saying I am actually going to buy one but I am wondering if an individual can get an Extended Validation SSL certificate?
I know this is intended for companies / organisations but would this technically be possible?
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I have implemented a login, and session, procedure for a web app and I am wondering whether what I have implemented is secure enough.
The authentication is based on login password on https. If the login succeeded the server returns a randomly generated token the server stores and sends with any https post request it makes. The server verifies the received token is the one generated for that userid.
The token has a timeout.
Is this procedure secure enough? what weaknesses does it have?
UPDATE
the problem is that it seems sessions are not supported by mobile applications (i.e. Android, iOS) and I have had to develop my own kind of sessions. However I am a bit afraid it is not secure enough.
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Suppose a given random number generator has poor entropy, and is compressible by any compression algorithm (zlib, bzip2, lzma, etc).
Specifically the issues with this RNG are:
Bad entropy
Bad seed size
Failure to use multiple sources of entropy
Reseeding only occurs once, at initialization, instead of at an interval. (less important than the issues mentioned above)
I'm asking this question so I can:
..estimate the loss of security created by bad entropy
..understand what aspects of encryption would be affected, and what wouldn't be affected (hashing, encryption, signatures, etc)
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The MD5 hashing algorithm is known to be vulnerable to collisions for a number of years now, see its Wikipedia entry. Still, I see that in many places throughout the web, MD5 is used to verify download integrity, e.g., the Ubuntu images. CMake's ExternalData()C feature description even says:
Note that the hashes are used only for unique data identification and download verification. This is not security software.
It seems that an attacker could append malicious data to a download, and then append a little more to provoke a hash collision.
Why do security concerns about MD5 not impact its popularity as download verification? Why have SHA1 (or similarly safe algorithms) not become the standard?
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We are hosting a site on a self-managed Digital Ocean VPS ("Droplet") that will be taking payments via Stripe using their stripe.js API. According to PCI, we have determined that we fall under the SAQ A-EP.
However, the SAQ A-EP (Part 2g) states that:
If merchant website is hosted by a third-party provider, the provider is validated to all applicable PCI DSS requirements (e.g., including PCI DSS Appendix A if the provider is a shared hosting provider)
What I am having trouble understanding is the following:
Since we are on a VPS provided by Digital Ocean, are we considered to be using "shared hosting" from a third-party provider? Or are we considered to be self-hosted, since the VPS is self-managed and Digital Ocean has no shell access to our box?
Does Appendix A need to be satisfied? If so, by whom?
If we are considered self-hosted, do we satisfy the following requirement (also in Part 2g), since our VPS has its own IP address and we are the only ones with access to the VPS?
Merchant’s e-commerce website is not connected to any other systems within merchant’s environment (this can be achieved via network segmentation to isolate the website from all other systems)
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I'm trying to do a Bruteforce attack on a handshake taken from my wireless network that is not WPS enabled. The reason I'm doing it is because I'm testing how strong a 10 digit phone number is as a password. I tried the following command
crunch 10 10 0123456789 | aircrack-ng -e NETWORK -b 60:C3:97:34:8B:E9 -w- hs/NETWORK.cap
But that took too long. I'm wondering if there is a way to start the attack after the first 3 digits of the password. Here they would be "760". I tried
crunch 10 10 7600123456789 | aircrack-ng -e NETWORK -b 60:C3:97:34:8B:E9 -w- hs/NETWORK.cap
But that starts with "777". Any help getting "760" first would be appreciated.
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The company I work for has recently moved to an external vendor for payroll services. We did an initial upload of data from our old system to the new vendor. I noticed that our employees that have apostrophes in their names (O’Riley for example) were no longer matching up with other systems. The new payroll vendor had removed the apostrophes. We are able to manually add the apostrophe back in via the web based front end, and running a report immediately after the change shows the apostrophe, but the character is removed by the next day.
When I inquired with the payroll vendor about the removed characters, I was informed that "The system will automatically remove quotes as they are problematic in the database itself." It was recommended that we use the grave (backward single quote) character instead because it looks similar to a single quote.
My question is this: Does the inability to handle quotes (single or double) in a database indicative of vulnerability to sql injection and is there a safe and legal way to prove or disprove this vulnerability?
This is a payroll system and I am hesitant to attempt to discover any vulnerability on the live system and I do not have access to a test system.
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There are various old questions on stack exchange which say that malicious code in file metadata can potentially be executed when the file is opened (here, here, and here for example). They are all from a few years ago however, is this still a valid threat with today's video players? If so, what steps can I take to make sure that my videos are safe to play?
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I want to become a pen tester/ethical hacker,what should I do in the beginning?
(I'm new to information security ,i have basic knowledge in python,will it be okay if I take CEH course,Any help is appreciated,Thank you all.)
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We have a project with 3 remote developers and myself, at the moment passwords (server logins, db passwords etc) are being shared via emails which are cc'ed to everyone,
Is there a normal workflow for this, we use git for version control, but it dosnt feel right to have our passwords in there (not that email is any more secure)
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Website here: alienvault.com
I've been trying out Spiceworks for about a week, seeing what use I get out of it. Today I log in and see an alert: "(my computer) has established a connection to suspicious IP 198.143.173.146" which apparently is some site called busedge.com and/or Singlehop, Inc. in Chicago (or spoofed there anyway). Anyway, I clicked "View Threat Details" next to the message and was taken to Alien Vault where I was given the option to "download a full report" yada yada obviously leading into buying something. Alienvault said that the site was actively malicious and had been the source of attacks.
netstat -f doesn't show that I'm connected to that IP, and the warning was from about 5am this morning.
My questions are: has anyone who has used this site offer their experience? Is it useful for threat analysis and possibly blacklisting IPs etc.? Is it a reliable source of information?
I'm in a small business network, not at home. I'm all for paying for services that may be useful, but I wanted to check with the community here to see if they've used it for connection monitoring/threat monitoring and what they thought about it. Also if someone has an opinion on if Spiceworks is just trying to get me to buy some stuff so they can get paid, or if suspicious IP warnings in their interface are really credible.
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Since GnuPG is available for Android, why does no one makes an app that encrypts every message using an RSA key and just swaps the keys with each "friend", so for example:
John has a limit of 100 friends.
John has 1 RSA public key.
Only John has the secret key.
People who would message John would only get his public key, therefore when they write to John, their message will be encrypted using John's public RSA key. When a message arrives, John's cellphone decrypts every message using his secret key. Keys will be stored on each cellphone and generated at their cellphone.
Please enlighten me.
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The following is a scenario for an attack where one website can impersonate another. I am told (including by this answer) that it's impossible, but I would like to understand exactly what prevents it.
Alice uses websites that fetch a trusted JS resource from Bob's server, using HTTPS to prevent MITM attacks. Bob's resource is popular, and he starts to use a CDN to distribute it. Now Alice's browser is making an HTTPS connection to a server belonging to the CDN.
The CDN uses Subject Alternative Names to share a certificate between multiple customers whose sites share an IP address on the CDN. Eve happens to own a site which is on the same certificate as Bob's (1). Eve knows Alice's favourite coffee shop, and can intercept signals on the wifi there.
Since Eve doesn't have the certificate's private key, she can't read Alice's HTTPS traffic. Instead, she waits for a request for the resource on Bob's site (2), and replaces it with a request to her own site, via the same CDN IP address that proxies both sites. The CDN server decrypts the request, fetches a malicious resource from Eve's site, and encrypts that using the shared certificate. Alice's browser sees a valid response from the CDN IP that it sent the request to, and seemingly has no reason not to accept it. Note that Eve doesn't need to modify the response by MITMing - the CDN server sends back the malicious content from a server behind it.
Or is able to hack into one. One of them is bound to be insecure.
Is the URL encrypted in an HTTPS request? If so, assume Eve replaces all requests going to the relevant IP address and bets on detection being unlikely.
I'm not especially familiar with SSL, so I'm willing to believe that something in that doesn't hold, but I'm not sure what, exactly.
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I carried out an arp poisoning attack from my virtual machine to real machine with cain and able and collected data with wireshark from real machine. While I was investigating data with wireshark I came across a data flow as picture.
What does it mean? I was expecting only an ARP storm. Can I use information in this picture to detect an ARP poisioning attack? Or cain and able using a different trick?
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I've been on a shared webhosting plan for 10 years and I recently moved all of my sites (various WordPress sites and associated plugins, all in PHP, a MediaWiki site, and a lot of static stuff) to my own VPS. Yay! Now I have no one to blame but myself for any problems relating to availability, performance, and security.
Regarding security, I was auditing 'netstat' output on this Linux-based VPS today and noticed that I had an established connection to port 443 (HTTPS) on a different server. I figured out what DNS name this IP address resolves to and hit the googles. This domain is only associated with monetary scams and fraud.
So this HTTPS connection is just hanging around. I visit the site and the root page is a small bit of JavaScript that collects some basic info about the user's browser and screen size and then redirects to a second page on the site that plants a cookie.
I ran lsof -i and determined that one of the Apache processes on my server has established the connection to the secure server.
Any idea what might be going on here? It seems pretty clear that something shady is happening. My best theory is that an attacker is hijacking an Apache process which, in turn, is dynamically requesting JavaScript via an encrypted connection and injecting it into outgoing pages.
Other data points: I have searched through all my files and can't find any trace of this DNS name or its IP address; however, I know that's not conclusive evidence because I've seen JS-based malware that can obfuscate URLs pretty easily. Also, I have checked all of my computers which have been accessing my various sites and I can't find any trace of the cookie that the JS would be planting (which could just mean I hadn't hit the suspect Apache process yet).
Always the programmer, I wanted to try to reproduce the problem, so I rebooted the server and I haven't seen the connection get established again.
I have some ideas about mitigation or tracking (block connections to the bad server, either via firewall or the /etc/hosts file; redirect HTTPS requests to my own system with a spoofed cert just to investigate the network transaction if the same circumstances arise again). It seems really odd that the connection was left open (when it could just fetch the page once and be done), but maybe this was an errant condition and it wasn't supposed to remain open.
Sorry if this is a lot of detail, or if I'm overthinking something simple. I'm just being paranoid about taking care of my little slice of the internet. I was hoping to see if these details set off any familiarity alarms.
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The report from Hold Security says that 1.2 billion sets of credentials are in the possession of this party. I have a feeling that this report may be a hoax or a partial hoax due to grammatical errors ("while we getting our full service ready") and self-advertising of their electronic identity monitoring service. If it is true, how should I respond to this mass credential theft? The report recommends identity protection services but would it be enough?
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Can we use the tools such as P0f, OSSIM and other passive fingerprinting tools to build a comprehensive network topology of how the devices are interconnected ?
or is there a passive finger printing way of building network topology ? without any active probing, traceroute, nmap etc
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Personally I want to call the element _DO_NOT_give_this_security_thingy_to_anybody_ever. An example scenario is some clever social engineers want the user to run a malicious "add a friend" and find the CSRF token stands in the way.
But is it worth it?
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I have data coming in the form of XML with certain XML attributes being encrypted. I am very new to encryption/decryption. So I would like a detailed explanation on how to find the encryption algorithm, if at all there is any applied on this data. Or is it some other form of encoded format? Please ask any question related to data, I would be more than happy to help on that. Sample encrypted data looks like this:
7b5c727466315c616e73695c616e7369637067313235325c64656666305c6465
666c616e67313033337b5c666f6e7474626c7b5c66305c666e696c2054696d6573204e657720526f6d616e3b7d7b5c66315c666e696c5c
66636861727365743020417269616c3b7d7b5c66325c666e696c5c6663686172736574302054696d6573204e657720526f6d616e3b7d7d
0d0a7b5c636f6c6f7274626c203b5c726564305c677265656e305c626c7565303b7d0d0a5c766965776b696e64345c7563315c70617264
5c6366315c66305c667332305c7061720d0a5c6366305c6631204c6f74204e696e65202839292c206f66204245415220435245454b2050
4f4c4f2052414e43482c20616e206164646974696f6e20696e20456c6c697320436f756e74792c2054657861732c206163636f7264696e
6720746f20746865206d6170206f7220706c61742074686572656f66207265636f7264656420696e20436162696e657420432c20536c69
6465204e6f2e20343535206f662074686520506c6174205265636f726473206f6620456c6c697320436f756e74792c2054657861732e5c
6366315c66325c7061720d0a7d0d0a00
|
I have a Gmail account. Unfortunately I have sent an email from my Gmail account. How I can stop or back this email ?
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Android docs lists a number of places to store data here.
To what extent can Google access data in these places assuming the developer does not want them to have it?
In other words, if I save a private piece of data in an app that I make in my "private internal storage", and make no use of Google Services (Play, Maps, etc.) whatever, does Google still have access to that data somehow? Does my carrier?
Does the answer to this change if I'm using Android's own Keystore to encrypt that data?
Note that I'm not talking about a physical or software compromise of the device here, I mean legally. What do they say, what might be the case (post-Snowden), what probably is the case.
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My web-app takes some configs from the user and saves into an XML file (it was not done to stop XSS). The input is XML encoded so that the ",& ... and such characters don't break the XML structure.
So is there a need to have another layer of XSS filter or will this way of saving the data automatically stops XSS attacks.
I'm aware of the fact that this attack depends on lots and lots of other factors such as rendering the webpage but lets confine the discussion to the following code snippet, however since the way I'm going to print the data very from time to time you are free to modify
echo "<h1> Hello ".$name."</h1>" to show me any wrong ways of printing data.
$data = $_POST['malicious_user_supplied_data'];
$xml_encoded_data = xml_encode($data);
write_to_xml_as($xml_encoded_data,"config.xml");
------ config.xml --------
<user>
<name><script>alert("BigBang")</script></name>
</user>
--------------------------
$name = get_name("config.xml") // would return <script>alert("BigBang")</script>
echo "<h1> Hello ".$name."</h1>" // which on the browser would print <script>alert("BigBang")</script>
Please show me some working examples where the above XML filter can be broken, if there are any.
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Doing an integration with an online payment provider. Payment provider will be making a web request to my server to provide some information about the basket content. On my end there's no payment processing involved, I only need to be able to capture the basket information along with the merchant ID. The payment provider will be acting on behalf of multiple eCommerce merchants in capturing and processing credit card details.
Security requirements:
I need to be able to verify that a request has come from a specific
merchant
I need to be able to verify that the message hasn't been tampered with
I need to be able to validate the client time stamp
Few alternatives that I have.
HMAC Signature
Payment provider to generates a HMAC signature (SHA-256). (With a pre-agreed signing key per Merchant) StringToSign = MerchantId + BasketInfo + Timestamp
Payment provider sends the above signature along with MerchantId, BasketInfo and Timestamp in clear text in a HTTP post.
Signature is verified on my end
Public key encryption along with symmetric encryption
SymmetricEncryptedText = AES_Encryption( BasketInfo + Timestamp) using a pre-agreed symmetric encryption key
TextToPublicKeyEncrypt = MerchantId + SymmetricEncryptedText
FinalEncryptedText = Public Key Encryption using my public key (TextToPublicKeyEncrypt )
FinalEncryptedText is sent in HTTP Post
On my end, FinalEncryptedText is decrypted using my private key. This gives me access to MerchantId + SymmetricEncryptedText
Decrypt SymmetricEncryptedText using MerchantId specific symmetric key
Symmetric Key Encryption
StringToEncrypt = BasketInfo + Timestamp
EncryptedText = AES Encryption (StringToEncrypt )
MerchantId and EncryptedText is sent by payment provider in HTTP Post
EncryptedText is decrypted using the MerchantId specific symmetric key
Appreciate you could shed some light on evaluating these options (Or any other suggestions) All communication is using SSL/TLS. So a man in the middle attack can be ruled out.
HTTP Posts happen through client web pages using a JavaScript AJAX call. So any token generated using above schemes will need to be generated and included in client side JavaScript. (Which enables an end user to be able to see the tokens on their web page source)
In my view, Option #1 and #3 are of the same nature. In Option #2, due to public key encryption, MerchantId is not shown on plaintext on user's HTML source. But does it really make #2 more secure due to MerchantId not being visible on user's HTML source?
Apologies in advance for the lengthy question. Let me know if any clarifications required.
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I was just reading about CRIME which is an attack to steal sensitive information by creating requests. Could this attack be mitigated, if the Server wouldn't send the client the actual session key to save in a cookie, but a random generated string, which maps to the session key? On each request (or every 100 requests) this random string is generated anew, so the client will have an ever-changing secret in his cookie.
This would make any attacks which require many requests which contain the same secret very difficult and would also provide the benefit that each of the random strings is only valid for a very short time...
Are there any obvious downsides to this approach? Or anything which wouldn't actually make it safer than today methods ?
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I'm working on a always online mobile game (native android/iOS app with Unity) and i would like to be able to authenticate the player without requiring any login/password at the beginning. For those who know, i try to achieve a similar authentication scheme as famous Supercell games (Clash of Clans, Boom Beach, etc..)
What i have in mind:
The very first time the user launch the game, a request to the server for a new account is done, the server send back a UUID.
This UUID is stored in the device (should i crypt or hash it ?).
When the user start the game i authenticate him with a token (UUID+timestamp+hmac(sha256, username+timestamp, K)). Is it better to generate a temporary session token (stored in the database) or could i use the previous token for all the requests after authentication?
For each request i send token+params+timestamp+hmac(sha256, token+params+timestamp, K)
And every communication will be over SSL.
is it totally insecure ?
NB: In the game you will be able to do in-app purchases and in this case the first time you try to buy something you will have to bind your game with your GameCenter or Google Play or Facebook accounts. This information will be store in the database. Should i use these accounts to authenticate if it's possible?
As you can see, nothing is clear in my head and i'm definitely not a expert in security. So every little advices will be appreciated.
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When we create a Google account, Google tells us whether an account with specified username exists or not.
Doesn't that lead to user enumeration?
Why not let users fill other information first, pass the CAPTCHA test, and then choose the email address after passing the CAPTCHA test? Would this really frustrate users?
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Firstly, if a site is PCI compliant, and new references to a 3rd-party file (e.g. image, Javascript, CSS, etc…) via http:// instead of https:// are added, does it violate PCI compliance?
Secondly, would adding a reference to a third party js library over https validate PCI compliance?
Thanks
|
I have a question and answers site. I have an admin section. From that section I can delete users, threads, responses, and edit various other things. I have some simple code at the start of the admin page:
if(($session->protected_page_security()) == FALSE ||
($session->is_administrator() == FALSE)){
$session->logout;
redirect_to('../index.php');
}
A session class has the following methods....
public function protected_page_security() {
if(!$this->confirm_session_is_valid() && !$this->check_login()){
return false;
} else {
return true;
}
}
public function confirm_session_is_valid() {
$check_ip = true;
$check_user_agent = true;
$check_last_login = true;
if($check_ip && !$this->request_ip_matches_session()) {
return false;
}
if($check_user_agent && !$this->request_user_agent_matches_session()) {
return false;
}
if($check_last_login && !$this->last_login_is_recent()) {
return false;
}
return true;
}
public function request_ip_matches_session() {
if(!isset($this->ip) || !isset($_SERVER['REMOTE_ADDR'])) {
return false;
}
if($this->ip === $_SERVER['REMOTE_ADDR']) {
return true;
} else {
return false;
}
}
public function request_user_agent_matches_session() {
if(!isset($_SESSION['user_agent']) || !isset($_SERVER['HTTP_USER_AGENT'])) {
return false;
}
if($_SESSION['user_agent'] === $_SERVER['HTTP_USER_AGENT']) {
return true;
} else {
return false;
}
}
public function last_login_is_recent() {
$max_elapsed = 60 * 60 * 24; // 1 day
// return false if value is not set
if(!$this->last_login) {
return false;
}
if(($this->last_login + $max_elapsed) >= time()) {
return true;
} else {
return false;
}
}
public function is_administrator(){
$administrator_ids = array("164");
if(in_array($_SESSION['user_id'], $administrator_ids)){
return true;
} else {
return false;
}
}
USER_ID = "164" is an administrator.
My question is this:
Do you think it is unwise to have a link to the admin section on the site (even if only shown for me, when I log in)? If someone can gain access to this page, they can bring down the entire database. Is it wiser to not have any link and just type the address in as a url?
I apologise for the simple question -
I am guessing it is possible for someone to find out (hack) the site file structure and "see" that there is an admin section regardless of whether there is any link to it right so maybe my question is moote.
|
The ISO27001:2013 standard (and ISO27002:2013 guidance) requires that use of "utility programs" that might be capable of overriding system and application controls should be restricted and controlled (A.9.4.4).
I've looked, for example, at http://en.wikipedia.org/wiki/Utility_program for inspiration and am finding it difficult to decide what might be considered a "privileged utility program", as most could be "dual use", i.e. if used without privileges they would be safe (and useful!), but with elevated user privileges they could introduce risk.
Is this intended to be a policy around setting access permissions for utilities?
What policies do other organisations have in this area?
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First time 'asker' on here, but wanted to say thanks to how much I've used this site and reading answers to questions I've had!
Anyway, lately I've been having issues with a customer of ours who's server is failing the PCI Compliance scan from Trustwave. The problem in particular is with OpenSSH being vulnerable and needing to update to the latest 4.4. However according to the CVE numbers they provided, it looks like the version the server is running has been patched. I could be reading it wrong, but from what I can tell there isn't a problem.
This is what the initial report said:
Port: tcp/xxxx
OpenSSH prior to version 4.4 is affected by multiple vulnerabilities
that may allow for a remote attacker to execute arbitrary code on
the affected device.
This finding is based on version information which may not have
been updated by previously installed patches (e.g., Red Hat "back
ports"). Please submit a "Patched Service" dispute in TrustKeeper
if this vulnerability has already been patched.
CVE:
NVD:
Bugtraq:
CVSSv2:
Service:
CVE-2006-5051, CVE-2006-5052
CVE-2006-5051, CVE-2006-5052
20241, 20245
AV:N/AC:M/Au:N/C:C/I:C/A:C
ssh
Evidence:
Match: '4.3' is less than '4.4'
Remediation: This issue was fixed in OpenSSH version 4.4. Upgrade to a
recent/stable version
Patches:
http://www.openssh.com/
So we filed a dispute with the following information from our server:
[root@host ~]# rpm -q centos-release
centos-release-5-10.el5.centos
[root@host ~]# rpm -qa | grep -i ssh
openssh-4.3p2-82.el5
openssh-clients-4.3p2-82.el5
openssh-server-4.3p2-82.el5
And all they responded with was this:
We have denied this dispute based on the information provided. The
information provided does not appear to be related to the vulnerability that
this finding is regarding.
According to the CVE database links below, aren't we running a patched version of OpenSSH?
https://access.redhat.com/security/cve/CVE-2006-5051
https://access.redhat.com/security/cve/CVE-2006-5052
If not, where am I getting turned around at? Thanks for your time and any input would be greatly appreciated!
EDIT:
I ended up submitting the following, which apparently was good enough for Trustwave to believe me when I told them our releases had been backported.
# rpm -q --changelog openssh-server-4.3p2-82.el5 | grep "CVE-2007-4752"
- CVE-2007-4752 - Prevent ssh(1) from using a trusted X11 cookie if creation of an
# rpm -q --changelog openssh-server-4.3p2-82.el5 | grep "CVE-2006-5794"
- CVE-2006-5794 - properly detect failed key verify in monitor (#214642)
# rpm -q --changelog openssh-server-4.3p2-82.el5 | grep "CVE-2006-5051"
- CVE-2006-5051 - don't call cleanups from signal handler (#208459)
# rpm -q --changelog openssh-server-4.3p2-82.el5 | grep "CVE-2006-5052"
- fix an information leak in Kerberos password authentication (CVE-2006-5052)
CVE-2008-1483: This has also been patched in Red Hat/CentOS releases (https://access.redhat.com/security/cve/CVE-2008-1483). To be sure, we have disabled X11 forwarding in SSH as it shouldn't be needed anyway.
|
I sent emails out that contains an email registration confirmation link:
http://example.com?create=email%3Djay%40gmail.com%26confirm_key%3D53e321f97c145
I do not hash the link above. Before I sent an email containing this link, the user registered as a new member. Email address is inserted as a new record in the database together with a confirm_key.
So in my database there are two fields that are first filled up email and confirm_key. The confirm_key is generated by the PHP function uniqid().
My question is, what are the security risk in using this method, if any?
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I am using Ubuntu 13.10. If my laptop is infected with malware, can I get rid of it by creating a live usb on it and using that live usb format and re-install the ubuntu ? I mean is it possible that malware will find its way in live usb and hence infect the re-install ? If yes, how to get rid of it ?
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I have found an XSS vulnerability on the subdomain of a site I am testing, and using it I can set cookies for both the main site and all it's subdomains.
My url currently looks like this:
http://s1.example.com/u/%22%3E%3Cmeta%20http-equiv=Set-Cookie%20content=%22sid=1234;%20path=/;%20expires=Thursday,%2020-May-15%2000:15:00%20GMT;%20domain=example.com%22%3E
The issue is that for some reason or another, the character "/" is filtered out (no other characters are), meaning that although I can set cookies to the main site and all it's subdomains, I can only set them to the path /u/ as that is where the attack is launched from on the subdomain. Is there any way to set the path to / without actually using the /?
Thank you very much for any help!
|
I am working with a website that sends API requests.
I would like to write a client to make the requests myself, but in order to do so I would need to first see the request payloads. However, the connection is secured and therefore I can't see the data in wireshark just like that.
I found out that Wireshark supports SSL decryption: http://wiki.wireshark.org/SSL
However, it doesn't explain how the private key file should be obtained or generated, so I went and looked around and found this blog entry: http://blog.stalkr.net/2010/03/codegate-decrypting-https-ssl-rsa-768.html
After finding the appropriate packets as shown in the images, I exported the certificate, but unlike the challenge they were doing, the connection established for me uses RSA-2048 and does not provide the factorization (I'm assuming real certificates do not provide that, only the ones for games and such).
Is it possible for me to decrypt HTTPS packets that are sent to 3rd party websites?
How would I generate the key file required?
|
Say I have a private service that exposes sensitive information (PHI) via a REST API, and that I want to permit access to it from only one other service.
Is it enough to partition these services into different security groups and restrict inbound traffic only to the calling service? Would this type of authentication be HIPAA compliant?
|
While writing an answer to this question on Server Fault, a thought that has been bouncing around my head for quite some time resurfaced again as a question:
Is there ever a good reason to not use TLS/SSL?
To further elucidate the question, I'm asking about the specific case in which things have been configured properly:
Performance:
Time to First Byte has been optimized.
The cipher list is small enough to avoid multiple roundtrips from server to client.
For mobile web applications, 2048 bit RSA server keys have been used as opposed to 4096 bit keys to lessen the computational load on clients.
SSL sessions have a reasonable lifetime to avoid regeneration of session keys.
Security:
Perfect Forward Secrecy
Hardened Cipher List
Don't use obsolete and insecure protocols like SSLv2 and SSLv3 (if possible; not using SSLv3 means that IE 6 can't access your site).
If done properly, is there ever a good reason to not use TLS/SSL for TCP communications?
|
I have noticed that every web site has the exact same behavior for their password reset pages. They send a link to your email using which you can reach the password reset page. On that page you enter the new password. So far so good. But at this point, they always prompt me to login again. Why? I just entered my password twice along with my login (email - of course this is done implicitly via the link). So why prompt me to login again? Is there a security reason for this that I am not seeing? Or is it just an old practice that seems to linger?
|
By definition, incognito mode shouldn't leave a trail of visited websites.
However, HSTS (HTTP Strict Transport Security) requires the browser to keep a database of hosts that have requested HSTS, and honor HSTS for subsequent requests.
This introduces a conflict and there are two possible ways of resolving it:
Browsers always honor HSTS requests made inside an incognito session, even when browsing outside of the incognito session.
Browsers honor HSTS requests made inside an incognito session for that session only.
Which of them is implemented in popular browsers?
Additionally, as discussed in the comments, do HSTS requests outside incognito session affect requests inside incognito session?
|
Are there any products that let you see and set IDS [Intrusion detection system] on router or any another hardware that is connected to the router?
All the ones I have found of them are Operating Systems like security onion, alien-vault, aanval. All of them are Linux distributions.
Is there not any another hardware IDS that I can connect to my router or is the router itself?
I ask that because it's much more easier than installing and operating virtual OS. It will also slow down the computer and the logs can be seen only by typing in the browser 192.168.1.1[for example].
|
I want to harden the security of my host system and side by side running virtual machines while testing some files for malware in one of the virtual machines.
Here comes a list of questions that I hope you can answer.
- Network Adapters
One thing that I am worried about is the possible spreading of malware from one virtual machine to another. Most of the virtual machines i am executing side by side at the moment are using the same network adapter. Could I somehow minimize the risk by allocating a separate virtual network adapter to the virtual machine I am using for malware testing purposes?
- Separation of Networks
I have read about separating the networks in some other threads.
Could I achieve this by connecting an additional network card to my pc and connect the machine that i use for testing the malware to one of the cards?
Furthermore I have read that one way to achieve separation would be to disconnect the machine from the network.
For my work the internet connection inside all virtual machines and inside the host system is essential at all times so I will have to exclude this possible solution.
- USB Device Drivers
Studying another interesting thread covering the same subject I have come across the claim that a mouse driver could possibly allow a buffer overflow attack.
Here is the link to the addressed thread, the post was created by Tim Williams.
Could somebody please explain if the mousedriver would have to be installed inside the guest system or would it be enough to have it running on the host system to cause the vulnerability?
- Mouse integration
Furthermore I have assimilated the information that the mouse integration (the plugin or option that makes mouse movement from the guest to the host machine flawless) could be a possible vulnerability. Is it really better or even necessary to disable this option to harden the security?
- Separating CPU Cores.
Do I have to worry about the guest VM using the same CPU cores like the host system? Is there a way to allocate for example one CPU core to one VM?
|
I am currently using a technique where I send the username/password in cleartext (using https) to the server, which then does bcrypt and compares to the db. Standard practice.
It is considered safe.
Would sending bcrypt hash to the server for checking be equally safe?
The point of bcrypt is that it is computationally expensive, so that stolen hashes cannot be brute forced (or would take a long time). With the client sending the hash, i think this still holds true.
So, the question is, would this technique compromise my network's security in any way?
-- Edit
I would like to do this because it reduces the computational power the server needs. Doing moderately expensive things on the client is never a bad idea.
|
I subscribed to a VPN service recently, and installed wireshark to take a look at the traffic sent from my computer.
Practically all of it goes through UDP protocol, encrypted. But there are two HTTP requests that are sent through TCP, not encrypted. One of them comes from an Firefox extention that updates imageboard threads, and it's GET request has the thread's URL and cookies, so that's an issue. The other one is from jQuery and has the website it's from in "referer" and a session cookie. The source of these requests is the VPN's internal IP address, but still, they're sent unencrypted.
Is that normal firefox entensions and jQuery behaviour? Why can I see the data they sent through wirehsark? I thought literally everything would be sent encrypted by the VPN.
|
If you worked in a big company that was very security conscious, would you build a product based on PlayFramework2 underneath? Since it does automatic dependency resolution at load time, aren't you placing a lot of trust in some possibly untrustworthy source of updated libraries?
Why would you trust it? How do you know that the libraries it's downloading from the wild are safe? Wouldn't it be possible for a hacker to compromise the source of the libraries, injecting some unknown code into it?
|
I found today that Google allows you to reach its search engine and submit searches over non-https connection.
Visiting http://google.com, results in a redirect to the URL https://www.google.com/?gws_rd=ssl
Attempting to visit http://www.google.com/?gws_rd=ssl (note, the protocol) results in access to Google over non-HTTPS connection.
Why does Google allow this?
|
I would like to know if I can use of PGP to ensure SOAP webservices confidentiality?
I don't want use SSL, it's kind of slow mechanism to make a tunnel for high throughput data transaction.
I though cypher data using a symmetric key, the key will be encrypted to by a asymmetric public key. And push the message in the network, just the intended receiver can read it.
Is it a good fair pattern for web services?
Any help will be greatly appreciated.
Regards
|
While reading this page about Public-Private key encryption, I asked myself a question about digital signature:
Alice wants to sign a message for Bob; she uses her private key to sign the message. Bob receives it and uses Alice's public key to generate the signature and checks that it's the same as the one that Alice attached to the message.
If I'm a pirate, I can intercept Alice message, and use Alice's public key to generate the signature too, no? If I'm right, it means that I can change Alice message, uses Alice's public key to generate the new signature and send this one to Bob, instead of the original one, no ?
There must be something wrong in this logic, but I don't see where...
|
I've recently spotted that DVL (Damn Vulnerable Linux) has gone inactive. My first question is what happened to cause them to stop releasing it?
Secondly, I have found some references to other testing environments, but was curious if there was an official/unofficial replacement for DVL that provides a large test bed for pentesting learning?
|
Some corporate applications are most useful when they are accessible from the internet. Outlook Web Access comes to mind.
Those application usually have a user directory (usually LDAP) in the corporate environment that serves other purposes, like desktop authentication or authentication to some other internal only service like an HR portal.
Using the external application, it is often possible to lock an internal account by trying to guess passwords by brute force. A targeted manual attack also works. Mitigating factors include not divulging user names, and unlocking accounts after a few minutes.
Seeing how frequent we see this combination, how can I evaluate the risk of locking an internal account by using an internet facing application? Is the risk small enough, and is the benefit high enough so that everyone can accept this risk?
|
Currently we are using Teamviewer 9. We have a couple of desktop machines that are locked down in the following manner:
1). The shell is no longer explorer.exe, it is a custom program we have created.
2). The OS is Windows 7 embedded, latest version, latest security patches.
3). The user logs on one of two ways: Admin mode which allows the windows shell and full computer access for troubleshooting, the other way is via the user logon which runs our custom run software and prevents the user from running the windows shell.
We found some holes though. At various mostly predictable times (when the support person exits a Teamviewer session on a locked down computer with the locked down user logged on) the Teamviewer dialog pops up on the client computer. In this Teamviewer dialog there is an options button that looks like a little gear icon. This icon would be the same as the options under the Extras menu on a regular Teamviewer panel (ours are customized and hence only shows a gear icon). When the user enters this settings dialog and chooses the video option on the left and then presses the select image button, the user can then enter cmd.exe (which will run a command shell), enter explorer.exe to run the shell. If they run the cmd.exe or explorer this will allow them to run IE, or ftp.exe.
Since these machines are internet connected via cellular modems we would rather that the user not be able to run these programs. Previous experience has taught us that these users log into their own Netflix accounts and watch movies and various things like that, which when run via cellular data connections could be very expensive in a very short period of time.
We investigated the possibility of using the group policy but from what our research has shown us the group policy only works if the shell is running. We could be wrong of course, but that is the information I have been given while making this post. Now if we could lock the shell down to the point where it could do NOTHING but run the program we want it to run including anything from USB while the locked down user is logged in, we would consider that, but that level of lockdown did not seem possible from our research.
If anyone knows of some good documentation on achieving this level of lockdown on a computer (similar in most respects to the level of lockdown you would want to see on a bank teller machine) we would be most interested in this information.
|
About two weeks ago, I had to reply to an urgent email (gmail) on my Android phone with the Gmail app.
Unfortunately, my VPN client refused to work that day (Private Internet Access Android Client), so I had to risk it and connect to a public wifi hotspot at a restaurant to reply this email of mine.
Now, I have been bombarded with spam with that gmail account I used to reply the email.
I have changed the password to this Google account mentioned the evening I returned home that day.
Is there any way to stop the spam? I used to have no spam email coming into this account.
|
I stumbled upon an interview with "the grugq" in which he is talking about how hackers anonymize their traffic, i.e. hide their original ip address (- this is also what I will mean by "anonymizing" in what follows). He states that
The old idea was to have a lot of boxes in different countries so that
it was legally very difficult to get all the records together. These
days, things are more sophisticated than those old style bounces,
though. Before you used to have do log-ins to loads of boxes to do
your bouncing. Now there’s packet routing software, so that rather
than running a session from box A to box B to box C, you install
software on a load of boxes, and then you have some packets which get
routed from box A to C to target, and the other packets go from box B
to box D to box A to target, and so on.
(http://www.csoonline.com/article/2121184/network-security/where-is-hacking-now--a-chat-with-grugq.html)
Since I'm rather a programmer than a network expert I would like to know:
What kind of routing software is he talking about? Do you need "special" software for that kind of routing or can you achieve that with standard linux tools (given that you can load necessary kernel modules, change iptables rules etc.)?
Are there any special routing algorithms that bounce traffic with the aim to anonymize it? As far as I see most routing algorithms aim at finding the "best", i.e. fastest (or, more abstract, "cheapest"), routes between source and target what may not be needed when your aim is to bounce traffic between different nodes to hide its origin.
The routing reminds me of what Tor is doing, but there are probably other solutions than Tor for that kind of task, since Tor would seem to be a kind of overhead here (and is limited to 3 nodes).
Thanks!
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It's a conceptual question:
Suppose i want to separate NAT and firewall, can it help to my security?
INTERNET >>>> NAT >>>> Firewall >>> MyNetwork
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I understand that CAs issue certificates based on common names (CNs) like www.amazon.com and that certs are not based on URLs like www.amazon.com/stuff.
How is it that when I go to www.amazon.com, it is not secured and when I press Log In, the connection is now SSL-secured? I could understand if the login link redirected me to a site like login.amazon.com where there was an SSL cert for the sub-domain... But the login page on Amazon starts with www.amazon.com which is not secured when you go to it without logging in.
This is the exact login link:
https://www.amazon.com/ap/signin/186-8075346-0703735?_encoding=UTF8&openid.assoc_handle=usflex&openid.claimed_id=http%3A%2F%2Fspecs.openid.net%2Fauth%2F2.0%2Fidentifier_select&openid.identity=http%3A%2F%2Fspecs.openid.net%2Fauth%2F2.0%2Fidentifier_select&openid.mode=checkid_setup&openid.ns=http%3A%2F%2Fspecs.openid.net%2Fauth%2F2.0&openid.ns.pape=http%3A%2F%2Fspecs.openid.net%2Fextensions%2Fpape%2F1.0&openid.pape.max_auth_age=0&openid.return_to=https%3A%2F%2Fwww.amazon.com%2Fgp%2Fyourstore%2Fhome%3Fie%3DUTF8%26ref_%3Dnav_signin
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In older versions of Android, when connected via USB the default behaviour was "Charge Only". This allowed the device to charge via USB without exposing its file system to the device providing power, often a computer.
In newer versions, this security feature seems to be missing, introducing a vulnerability whereby the file system is now exposed to the powering device.
Is there a way to re-implement this "Charge Only" security feature so that the Android's file system remains hidden or encrypted even when connected to a computer via USB for power?
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What are the top security concerns when setting up a PXE (Preboot Execution Environment) booting environment, ordered by severity of a possible exploitation?
Things that I thought of are (in no particular order):
Rogue DHCP takeover
Man-in-the-Middle attacks on the NBP load over TFTP
The question is meant to look at the general protocol and its possible weak points and is not restricted to a certain setup concerning equipment or attacker.
If anyone wants to help me bring this question in a more suited format, you are welcome.
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I am trying to pentest a dummy website that has a form with a TEXTAREA input on one page.
When the form is submitted, the contents of the form are displayed on a second page.
However, the second page that receives the POST input, filters it to replace ", <, > and & with ", <, > and &.
The second page also has a:
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
I used Fiddler to intercept the POST from the first page and modified the request header fromContent-Type: application/x-www-form-urlencodedto:Content-Type: application/x-www-form-urlencoded; charset=UTF-7
And changed the POSTed content to:+ADw-/font+AD4APA-script+AD4-alert(document.cookie)+ADw-/script+AD4
Hoping that it would decode to:
</font><script>alert(document.cookie)</script>
However, it didn't do anything and text showed up as it is. Also, the text-encoding of the second page was recognized as UTF-8. I guess that's because it has a meta tag in it's HTML with the charset set to UTF-8.
I want to know if there's a way this page can be exploited through XSS and if there is, what would be the input vector?
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The django docs tell us that our AJAX scripts should acquire the token from the designated cookie as in get_cookie('_csrf_token'). Can I rather print it to the HTML source, so that it's available to the JS context more easily?
<script>
var TOKEN = "{{csrf_token}}";
</script>
<script src="myscript.js">
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I am a novice to network security domain.
For one of our clients, we are trying propose a network model where an Apache proxy/web-server which will be the only one that is exposed into the DMZ(Demilitarized Zone) and application servers/DB will be inside the WAN. But the client is insisting on keeping an application server running out in the DMZ.
We know that its a security risk but we are not able to back ourselves by putting solid points across .
The questions I have are,
would exposing just 80 or 443 still compromise the security?
Can a hacker push bots or take control of the server and in turn reach the internal network?
What kind of security measures need to be taken given this approach?
Note: We are using Windows servers.
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I was looking through the OWASP XSS Filter Evasion Cheat Sheet, and there was one technique that was completely new to me:
& JavaScript includes
<BR SIZE="&{alert('XSS')}">
I tried out the following HTML:
<html>
<head>
<title>test</title>
</head>
<body>
<br size="&{alert('1')}">
</body>
</html>
on Firefox 31.0 and it didn't seem to work (i.e. no alert box). Did I miss anything, or is this technique only applicable to older browsers?
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I'm not into security and encryption at all, I'm just a Truecrypt user. So maybe it's a very noob-question, but I can't figure it out.
When I make a Truecrypt container, it will encrypt everything inside it. When I want to open the container, I open up Truecrypt, mount the file and type in my password.
Suppose my computer is stolen and the thief finds the container and is savy enough to recognize it as a Truectypt-container. All the encryption will do me no good, right? Because the only thing the thief has to do is crack my password, open up Truecrypt and mount the container.
So, although my files are encrypted, there seems to be a single point of failure: the password (which I make very strong ofcourse).
Are there any flaws in my logic?
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If I re-install Windows, will it ensure that all types of malware/spywares/rootkits and any other malicious software are removed from my laptop?
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Please if you cant answer this question, don't down vote it and the let others to discuss their opinions instead of closing it.
Yesterday I watched a collection of videos at YouTube for people who can hack a car which is parked 200 meter away from them, they can turn the car on/off and even use the benzene pedal or turn the steering wheel right and left even this car does not belong to any of them, what I want to know how such a thing can happened ?! it is possible to anyone to hack such a thing ?
These people also have a video which they hack the main big display in train station which has all the information about coming and going trains in that area and they replaced it with another picture by his mobile.
An explanation of what is happening is really appreciated :)
Thanks
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Can I get "hacked" by a Tor node?
My computer is sending packets through the Tor nodes and receiving packets from them as well.
Can I be sure that there are no Tor nodes that manipulate the packets sent through them and could infect my computer with malware?
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I know XSS is possible if the window.name is echoed onto the page, but from my understanding, this requires you to use an iFrame, but what if the page has clickjacking protection, stopping the page from being embedded in an iFrame? Is such an attack still possible? Here's example JQuery...
<script>
$("div").html(window.name);
</script>
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I have a case at hand as follows:
There is a number of clients in Internet (i.e. untrusted channel), initially in hundreds but growing in numbers.
There is a server doing processing related to these clients. This relation is established prior to this elsewhere, say a web portal.
The clients should be able to connect to the server via a piece of software (non-human operated, e.g. not a browser) over the internet to load the material so that channel is encrypted and that the server knows which client is connected.
There should not be an issue the clients could claim they have not requested the material when a connection has been made and the material has been transmitted. As an edit related to Thomas's question about not receiving material when they did: if I were to use plain password here, would there be a danger the password leaking more easily than the cert and someone else using it to obtain the material to be transferred? Though, I've thought about mitigatiging against such a situation by using this "sequence id" (see point 6 in the following list), which probably helps with or without certificates.
The client never accepts incoming connections. It only initiates them to this well-known server.
The ones operating the clients usually do not have their own certificates issued by some certificate authority.
The server processor program has a certificate issued by a certificate authority (e.g. Thawte).
Question: What would be a good way to accomplish this in a secure and a maintainable way?
As far as I know, there isn’t any PKI software that I can use. I've planned the following:
Let the clients download the piece of transfer software, say from the portal. The portal can include a settings file having a client id of some sort in it (and a, say, one-time password see point 4).
When the client installs the transfer software on the server it generates a self-signed certificate with the client ID in the CN. For instance makecert -r -n "CN=SomeClientId" -pe -ss my.
This software sends the thumbprint of the generated certificate to the server along with the client id and uses a one-time password it has obtained elsewhere (see point 1).
The server stores the thumbprint along with the client ID.
Now when transfer software connects to the server, it can check to which client it belongs via the transmitted thumbprint and the channel is secured.
For added security the server maintains a sequence number that needs to match with that of a respective transfer client. If they get out of sync, a breach is suspected and the very least the client needs both to go to the portal to reset the counter and reset in the transfer software (e.g. set 0 in the settings file).
Does this look like a sound arrangement? Would there be a better one? It looks like that if access of certain client needs to denied, all that is needed is to set a flag in the server database to indicate a certain thumbprint is not allowed anymore.
Whilst browsing through SE, I came across How to distribute client certificates without exposing private key?. Taking the cue from Thomas Pornin's answer, I see I could alter this process so that upon generating the certificate. As for an example:
Create someclient.inf file with appropriate parameters (in Windows, otherwise in other OSes, e.g. using openssl).
Do certreq -new someclient.inf request.csr to create the request file.
Send the csr to the server using the one-time password.
The server receives and csr file and creates the certificate, saves the thumbprint and sends the certificate back.
The client optionally installs the certificate with certreq -accept someclient.cer.
Another question: Would this bring additional benefits beyond the procedure I outlined initially (and is this a sound procedure)?
Additiona questions: It's unclear me as to how the server should do the signing. Which program? With which parameters? But maybe these should be another questions if this procedure is a usable one.
As a note: it could be I don't have access to all of the software on the command line or writing the code gets compplicated on the client end, so perhaps I'll need to resort to something like a BouncyCastle.
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I have a list of plaintext passwords that I would like to hash with various different hash algorithms (for educational purposes). As a minimum I would like to obtain hashes under MD5, SHA1, SHA256, (with and without salts), bcrypt, PBKDF2 and NTLM. Since hashcat supports all of these, I thought the simplest approach would be to run hashcat on the passwords with all the different algorithms.
However, to my astonishment (and frustration), I haven't been able to find a simple way of doing this in hashcat! Since hashcat is targeted towards breaking already hashed passwords, it requires a list of hashes, not plaintexts.
Thus, is there a way of simply running each algorithm in hashcat on a password in the clear - to obtain its hashed value?
Note: I don't really care if it's hashcat I use or not, I'm only looking for a simple way to hash some passwords with various different hash algorithms - minimizing the amount scripting I have to do myself. So if you have a better tool or approach, please share it.
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Q: Suppose an attacker knows the max allowable character length, n, for a website's passwords. Would it be smart for them to attack passwords of length n BEFORE length n - k (where k is small portion of n)?
Q: Suppose a website has max allowable password character length 32. Would it then be smart for me to choose a password of length, say, 31 or 30 rather than 32?
UPDATE: Asked another way: is there a known phenomenon of a mass of user passwords at n? And if so and knowing that, would attackers go after passwords of length n before length n - k? And if so and knowing that, would users be better to avoid passwords of length n?
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I understand why a hashing algorithm should be slow but is the method that makes it slow important to the strength of the hash? Everything I've read says that the algorithm should be computationally slow - hash the thing over thousands of iterations or concatenating it with huge strings to slow it down. This seems like it would put unnecessary strain on the CPU. Couldn't you just hash the password once with a good random salt and then just pause the thread for a set amount of time?
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Suppose I have this scenario:
User --> Inputs License Key --> I validate it --> If success, good, move onto main window. If not, prompt the user to reenter the license key.
The license key will not have activation or hardware ID verification. Just basically enter key and pass or not.
I am wondering about few things when it comes to license key validation.
1) What am I comparing the license key I get from the user to typically when someone performs a license key validation?
How does it determine if the key is valid or not?
What if I had an xml template that included what was needed to generate a key and that xml template had a public key. Would it need to include the private key?
Where in my code/when do I use a private key for validation?
2) After I validate the key and it's valid, I save it inside the datasbase.... If the user reopens the software, do I just do a check to see if a key is stored in the database? How do I perform a daily check to make sure the program is running a valid license? What is typically done in this scenario?
EDIT: More details.
Probably highly insecure but just talking about very basic license key validation using private/public keys.
No hardware ID or activation through server. No License. Just basic check if the key is valid or not.
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SHA-1 was standardized by the NSA. It appears to be possible to choose the constants in such a way that collisions can be derived easily. Yet, it is not easily possible to discover that the constants have been chosen in such a way.
Would it have been possible for the NSA to insert a backdoor into SHA-1 using this technique? Would there be any way to find out? Are there be any security implications regarding the standard SHA-1?
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I was playing with OWASP Mutillidae II and in one page I've found a vulnerability. In the address bar I've wrote something like this:
127.0.0.1/.../?page=text-file-viewer.php/"><script>alert("test");</script>
The alert box pops up, but I don't understand why? I know what happen if I put this code in an input form, but I don't know what the address bar do! How does the address bar process the string that it gets? Why does my code work if I put it in the address bar?
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So I just learned about SSLStrip now--I feel like I'm so late to the game. What I want to know is: If your site only serves content over HTTPS and hard fails on HTTP requests, with no redirect, are you still vulnerable? Can an attacker intercept your HTTPS request and perform the request "on your behalf", so-to-speak, and serve your browser an HTTP version, if you type into your browser's address bar? (Using either SSLStrip or some other attack?)
The TL:DR;
Below user10008 gives the answer. SSLStrip doesn't depend on the server's behavior, it depends on the client. If you can get the client to make the request over HTTP, instead of HTTPS, you can perform the attack, even if the server only supports HTTPS. HSTS prevents the browser from performing the plain HTTP request in the first place (on subsequent requests).
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I hope this question fits this stackexchange:
From what I understand, IPSec takes care of encrypting everything above the IP layer (transport, application). Does that mean that if I open a socket between two applications for, say, a chat, that my chat is "secure"? (in the sense that no one can alter the data sent by MITM / impersonate the other side).
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