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If I have a passphrase-protected SSH private key,
AND
if this passphrase is sufficiently random and long (say, 20-, 30-, 40-characters long, or even more!),
AND
if I make this private key of mine publicly available on the Net
THEN,
will it be practically possible for someone to be able to decrypt my private key from ... |
I'm currently generating a new gpg cryptographic key, and I'm using a new laptop for this. I can notice that the key generation step, which involves the random generation, is extremely quick, while I can recall that, on my old laptop, this process required a certain amount of time.
For a normal operation this should be... |
I'm working on a pen-testing project and still in the beginning but I faced a switch with only 80 & 23 ports opened. How can I use these ports to attack that switch ?
|
I am new to the IT Security field and am essentially a developer as opposed to a networking person hence the question may be a dumb one
I am writing a REST service exposed to the internet which accepts files to be uploaded to the server, and the size could be up to 5 MB. We have restrictions on the server side to not a... |
I've recently begun using Keepass for my personal password management.
I am setting it up to sync between my home PC, work PC and mobile device using dropbox.
I'm going "all the way", and have changed my passwords to 32 character mixes of letters, numbers and special characters. Even for stuff I commonly use, like my ... |
How to download data anonymously, were to store the data. I was reading a post on a forum and a guy was asking how do you download data anonymously and he asked how do hackers do it ,everybody started to be smart but nobody did know how. So my question is how to download data anonymously and how do hackers do it?
P.S. ... |
I'm working through OWASP's "WebGoat" (version 5.4) vulnerable web application, but I'm getting stuck on one of the earliest lessons which is to do with HTTP response splitting.
I've looked in all the hints and the solution (and even at all the tutorials dotted about the interwebs), but I still can't get it to work.
I'... |
I set up Google 2 Factor auth to use 2 Factor Auth with certain sites. But reading over the help suggests that Google 2 Factor Auth is only used to log into Google services like Gmail.
But when I log into Gmail, to does not ask for 2 Factor Auth code.
Is Google 2 Factor Auth used to log into Google services?
Where is t... |
I set up Google 2 Factor Auth to log into other sites. I see there are backup codes if you lose your device.
Are these used only to log into Google, or can they be used to log into other sites?
|
If you use Google Authenticator to log into sites using 2 Factor Authentication, how do you log in after you lose your phone?
Can you install Google Authenticator on another device?
|
I admit up-front that this question may be the result of unfounded paranoia. But I am concerned that uploading and downloading data in binary form opens the door to exploits that might not be possible if the data were encoded during transfer and decoded at the destination.
I will stipulate definitions because I see th... |
I have a dual-boot setup with Mac OS X Mountain Lion and Debian GNU/Linux Sid (fully up-to-date).
I installed gpg in OS X by executing brew install gpg. I then generated a keypair for myself to use.
The gnupg (and gnupg2, although this isn't the default gpg) and seahorse packages were installed during the Debian instal... |
The vehicles are fitted with a security system to track their movements and report it back to their owners if they are moved unauthorized.
My question is: can we have an additional security system or any third party system to monitor the existing security system? If so, how?
|
Is there a reliable way in PHP to identify a device that might be behind a Router (so the IP is not unique)?
Background: I have several embedded devices (self programmed & adaptable) that contact a webserver (php+mysql) with status updates. These updates are then - if the source is confirmed - saved to a database.
As ... |
I've noticed a few requests like this to a Rails application I am maintaining:
GET http://mydomain.com/?f=4&t=252751+++++++++++++++++++++++++++++++++++++++++Result:+%E8%F1%EF%EE%EB%FC%E7%F3%E5%EC+%EF%F0%EE%EA%F1%E8+85.17.122.209:6188;+%ED%E5+%ED%E0%F8%EB%EE%F1%FC+%F4%EE%F0%EC%FB+%E4%EB%FF+%EE%F2%EF%F0%E0%E2%EA%E8;+Resu... |
I have a URL to a flash file. Sample :-
http://abc.mydomain.com/Findme.swf
Now, there is a parameter called xmlpath as :-
http://abc.mydomain.com/Findme.swf?xmlPath=something.
Is it not that xmlpath is used to point to an xml file? If proper sanitization of the parameter xmlPath is not done, how can it lead to an X... |
I have a file that supposedly contains AES-256 encrypted data. The file was created using a proprietary program that claims to use AES-256.
I have tested decrypting the file with an open source program (openssl) and it works, I get my exact original file back.
Given this, is it possible that the proprietary program cre... |
What is the purpose of the "secret" that is displayed when you take the picture of the QR code to set up 2 Factor Authentication on a non-Google site?
Why would you need it?
If you save it, doesn't that defeat the whole purpose of 2 Factor Auth because anyone with the secret can get a login code?
|
Following on the heels of the previously posted question here, Taxonomy of Ciphers/MACs/Kex available in SSH?, I need some help to obtain the following design goals:
Disable any 96-bit HMAC Algorithms.
Disable any MD5-based HMAC Algorithms.
Disable CBC Mode Ciphers and use CTR Mode Ciphers.
To this end, the following... |
Assumed I have to following code in order to generate a random blowfish salt for saving a new password:
$blowfishCharacters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789./';
$salt = '';
$type = '2a';
$cost = '08';
$maxIndex = strlen($blowfishCharacters) - 1;
for ($i = 0; $i < 22; $i++) {
$... |
While reading up on view state as a possible means to prevent CSRF, I came across this Microsoft Security Bulletin which states:
An attacker who successfully exploited this vulnerability could read
data, such as the view state, which was encrypted by the server.
I had always heard that encrypted view state was secu... |
It is my understanding that PGP permits multiple public keys, and in SSL you can only extract one public key? Is this correct? Is there any brief high level run down between the two. I don't feel as if I ever really understood how SSL works, and I'd love to get a better understanding.
|
I currently use a lot of Remote Desktop Connections and even mRemoteNG and I am curious, do key loggers and other security threats have the ability to see what I type and do on the RDPs? Can they piggy back on the connections?
I am pretty sure that all keys will be logged but should the host machine in some way have a... |
Is it possible to create a route on your internet router which routes traffic unknown to null. So you basically dont even let traffic route into your firewall unless its approved? Can this help detour the ICMP pings which take down your circit?
|
I don't know much about how WPA algorithms work internally. Is brute-forcing an AP the only way to crack WPA? (or to get associated with AP)
Another question is about Reaver-WPS, what if an access point doesn't support WPS, or is disabled? Will Reaver work on such AP
|
According to PCI PAN can be stored in the database as long as strong cryptography is used. I couldn't find which cryptography is considered strong according to PCI. Here's the issue: I have PAN numbers stored as clear text in one of my databases, these numbers are gathered from a specific application (with set access r... |
I have two servers (one on Hetzner (I am calling it H) and other in my office (calling it O) ). I need to run a basic CRUD web service on O and the only consumer of the service is H. Data on O is sensitive user data. This is a temporary duct tape service which will go away in the future along with the need for the serv... |
I know there are 2 services of VPN (free and paid). Normally, free VPNs need money from somewhere and sometimes they can sell your information to any agency that needs it.
Now, if we are talking about a paid VPN where they use encryption and don't keep any logs or information about the user, IP addresses, or what you'r... |
Is there any way (standard, proposed or draft) that will allow for secure Caller ID over SIP / VOIP networks?
I have constantly heard that Caller ID is insecure when used over these services. Can anyone explain why Caller ID is insecure when used over these networks?
|
I will start off with saying apologies if this is something that has been asked 100s of times or is moot question within testing circles.
I have come across this article
I'd like to test this out but would rather do it on a real life scenario. I do not have access to a DB to create a POC and would feel far greater sen... |
After TLS 1.0, there have been a number of RFCs e.g RFC 5932, RFC 6430 etc. Is there any place where one can get an exhaustive list of ciphers for each of the versions. Or at least an exhaustive list of RFCs so that I can read and get the ciphers from each of them
|
The application which I am writing generates a 256 bit symmetric key everytime it wants to communicate with the server and encrypts the data and sends it to the server. This is to avoid storing the symmetric key on the machine. Now, to encrypt the symmetric key, I am using a 1024 RSA public key installed on the machine... |
I was wondering how bruteforce methods work from a code level. How does the code get access to a login page for example and insert information into the necessary fields? And is the code able to duplicate the system so that 3 attempts or waiting between guesses is no longer a problem?
|
If I sign a .NET assembly and do not give out my private key, how much effort would it take for somebody to crack the private key?
|
I was using Burp Suite for some testing and I noticed that they included the following string:
\";alert('XSS');//
as an attack string for an XSS payload.
How could this string be used to execute a XSS attack?
|
I'm thinking of implementing a salt recycling scheme on my user credentials database. The motivation behind this decision is that even if the attacker manages to get his hands on the database and has enough time to crack a password or two, by the time he does the salt will have been reset and his results will be usele... |
My project's backend is SQL Server 2005 and I need to install this to customers' systems.
The problem is when someone logs onto the computer, they can easily access the SQL Server with Windows authentication. How can I protect the SQL server from local logins?
|
i want to secure my web-server from hackers. what are the ways for secure my web server? . I need tight security. without admin permission no one can not access or hack my web-server
|
We're developing an online events calendar for a senior assisted-living facility.They want to record, in the system, the names of facility residents who attend each event. There would be no other information recorded except for the resident's name. Would this alone cause our system to have to comply with all 54 items o... |
Some pages of my website were vulnerable to SQL injection. The injection worked only when the user was logged in. I have now fixed this problem, and now I want to make sure that no similar problems remain. I have tried scanning with sqlninja and sqlmap but neither program has a provision to give website login details. ... |
So what is the use of protecting the ssh key with password when the notebook has full disk encryption? If someone is able to get the id_rsa then it is able with no effort (?) to get the id_rsa's password from memory, because it's stored in the memory in a cleartext format? (using ex.: ssh-agent)
Q: with FDE, is it wort... |
I am getting SSL: alert ["write"]: fatal : bad record mac from the OPENSSL logs during the handshake and Client is not sending the Application data and its creating the handshake again and again.
What could be the issue please anybody help me in this?
|
I was messing around with bcrypt today and noticed something:
hashpw('testtdsdddddddddddddddddddddddddddddddddddddddddddddddsddddddddddddddddd', salt)
Output: '$2a$15$jQYbLa5m0PIo7eZ6MGCzr.BC17WEAHyTHiwv8oLvyYcg3guP5Zc1y'
hashpw('testtdsdddddddddddddddddddddddddddddddddddddddddddddddsdddddddddddddddddd', salt)
Output:... |
I'm currently thinking about a web-app that can go offline (after being online) and still be able to provide authentication to the user securely.
(For example, in a multiuser environment, it's quite essential to prevent other users' access.)
Right now, I was considering a password-hash authentication with some salt, an... |
See X-Keyscore: NSA tool collects "nearly everything a user does on the internet".
http://www.theguardian.com/world/2013/jul/31/nsa-top-secret-program-online-data
Does anyone have a clue how they collect the traffic in the first place and whether they decrypt HTTPS traffic or not? (For example, by stealing the private ... |
I have the Tor Browser Bundle installed and have been using the Firefox Tor browser. If I attempt to download a file or email attachment I get the following warning
I understand that if I download an untrusted file containing a script it could reveal my IP address. However, I want to know if my IP address is still com... |
I have an interest in using EAP-TLS to authenticate both users and devices separately on mobile devices (phones, iPods, tablets, etc.).
My issue is how to delineate between user authentication and device authentication, since there is only one "account" on the devices, and multiple users per device. We are able to m... |
Recently a provider (of SIP trunking services) I subscribe to sent me a strange email. It claimed that someone in another country attempted to reset the password to my account and was unsuccessful in answering my security question.
The provider's response to this event was to reset my password.
Dear Customer,
We recei... |
What are some recommended practices for backing up SSL certificate private key files? I'm working in an environment where the public web servers are not backed up, because in theory the public systems could be rebuilt from data on the internal systems-- which they mostly can except for the SSL certificate key file whi... |
Can you guess how the NSA can read Facebook chats, while Facebook does use SSL encryption?
Requesting information directly from the Facebook HQ is possible (see also who betrayed Facebook in favor of the NSA), but if you read the details of this program you will see that they are talking about the raw TCP packages.
"en... |
I am new to IT Security and I have been tasked with coming up with input and output validation for ESAPI.
So for input validation, so far I got:
Data Type
Name
Email
Password
Address
Account Number
Zip code
Comm... |
Scenario : There is a persistent XSS on a page with the username information. The username is present three times in the page, is visible only once and the visible one is correctly escaped.
How would you hide the payload so that it is not visible when the username is displayed ?
My first idea was to change the text d... |
I'm considering using EC2 Spot Instances in an automated fashion (ie create a script that will request EC2 Spot Instances that will run unattended).
For this specific use case, I'm happy to lock down the security group such that there are no incoming connections allowed on the Spot Instances.
The only output of the scr... |
I have Unix systems (Solaris, Oracle,.Redhat etc.). I have to control all systems for security problem,bugs,patch,vulnerabilities.
I'm looking for security information for all security issues.
After that I'll update and check all Unix systems.
I need to take notification for Unix systems or I need admin panel for ma... |
My website has an iframe used for loading my client's websites (only 5).How can I make sure the iframe is secure? Also by editing iframe src It allows to load any other websites.How can I prevent it?
|
I suspect that my home router was been hacked (with firmware upgrade), so that I would like to build and buy a new router enough secure. Something that can prevent not authorized firmware upgrade. I don't think that a username and a sophisticated password are enough because these data can be sniffed or captured with a ... |
I posted this question Is a passphrase-protected SSH private key susceptible to a dictionary attack? a few days back.
An excerpt from the final answer:
With PKCS#8 + PBKDF2 and one million rounds (OpenSSL would need some
coaxing to produce that), you gain 20 bits (because 220 is
approximately equal to one million... |
I was faced with a question a few days ago, regarding how a RAT server can reach out through the firewall and connect to the client. This was something that I've never given any thought to before, so I was a bit perplexed by the question.
So, the question is, as previously stated, how the RAT server can connect to the ... |
This is the first time I encountered similar thing. When I log into the Twitter web site in Chrome (namely, the Iron version which is said to be security enhanced, but that does not matter here) in private browsing mode it automatically logs me into my Twitter account in the main browser window as well.
Is it a featur... |
Maybe I did not search for it the right way but I could not find the solution. Maybe I am misinformed but if I understand correctly I could use PUTTY to run any Windows applications through a proxy even if it does not have that feature.
Let's say I want to run Skype through a proxy using PUTTY. (Yes, Skype is more adva... |
We are currently developing a web application which involves map APIs. Most of the map API providers don't provide any SSL support (e.g. Yahoo! doesn't). What will be the security impact of using map APIs without SSL?
I am integrating the map API in one of my web pages. Is it safe to implement a website without an SSL ... |
I read an article by a stackexchange founder:
http://www.codinghorror.com/blog/2012/04/speed-hashing.html
It talks about: " two ATI Radeon 7970 cards generating nearly 16000 M c/s with MD5."
" the full range of a common US keyboard – that is, including uppercase, lowercase, numbers, and all possible symbols:
all 6 ... |
Suppose I have an application which does encryption using SSL and provided you cannot control what cipher suite is being negotiated, and assuming that I have some custom compression over the data before the encryption takes place. What would be the best mode of compression to be used? If I go ahead and use DEFLATE/GZIP... |
We're currently looking for a solution (hardware or software-based) that can monitor and audit all PHI viewing activity per new HIPAA rules. We use MS-SQL for our production database. We have the following requirements:
Can track inserts/updates/deletes/views of PHI
Works for both Database Users and Application Users
... |
I have a debit payment card, once it expired I received a new one. The card numbers look like this
Old card xxxx xxxx 1111 1111
New card xxxx xxxx 2222 2222
where x are the matching numbers and 1 and 2 are different (odd, but maybe the first 8 numbers are assigned to the particular bank/branch which I didn't change).
... |
Following on from CRIME, now we have BREACH to be presented at Black Hat in Las Vegas Thursday (today). From the linked article, it suggests that this attack against compression will not be as simple to turn off as was done to deter CRIME. What can be done to mitigate this latest assault against HTTP?
EDIT: The present... |
I'm looking for software libraries that support 1-2 oblivious transfer of a single bit between two parties.
Googling seems to bring up lecture notes, explanations, and research papers but not implementations.
I'd just implement it myself, but crypto is notoriously hard to get right. I don't know nearly enough about, sa... |
I built a simple server containing static files at /files/ and I'm attempting to discover them using automated tools.
I'm using wfuzz to brute force on the URL but is that the only way? Is there any other method for URL discovery, probably more effective that could compromise the privacy of my server?
What other techni... |
I tried using the web proxy functionality of OWASP Zed Attack Proxy (ZAP) to edit the response JavaScript and HTML. I tried to make a button get the attribute disable="false" instead of disable="". I can easily use the Firebug console to achieve this.
However, I want to use ZAP instead, and I set a breakpoint at the re... |
There are 2 machines - both running Windows Server.
Machine1 can access the internet. Machine2 cannot access the internet, but can access Machine1.
Machine2 needs to continuously access one external https GET URL on the internet. So the way I was thinking of doing this is by running a lightweight proxy server on Machin... |
I would be interested in advice.
Imagine a authentication mechanism where users are authenticated ONLY using
some code (e.g., one time password) which they receive (say as SMS) on their mobile phone?
Is it secure? I think it is not a good practice to rely authentication only
on such codes which come on mobile phone, be... |
Even though router knows you are always there, what are some other things we can do rather than changing MAC address
Ok the thing is there is wireless access point(router) and a user(owner of router) and another person who knows password and SSID of AP.
Is their any way to remain uncaught.
Can we clear router logs
wha... |
Here's the situation: the government of West Nauru is known to run a lot of TOR exit nodes and to collect a lot of data on the traffic, using extra large arithmometers to collate & correlate stuff.
Does it make sense to put ExcludeNodes or ExcludeExitNodes into the torrc file to keep the West Nauruan surveillance agenc... |
For a project at work I'm currently implementing a not too large webservice. For reasons of learning something new I tried making it a REST service, which then prompted the issue of authentication. I eventually settled on HTTP Basic Auth since it has the benefit of being supported by pretty much any HTTP library, even ... |
I'm one of the co-founders of plaintextoffenders.com. We recently received a submission for which I'm not sure if there is a means of attack or not. The site in question is a hosting/VPS/etc. company.
Once someone clicks on Forgot Password, an email is sent to the user's email address. It specifies a password reset add... |
Microsoft Exchange / OWA (Outlook Web Access) allows for three different types of compression (link for Ex2010)
Compression setting Description
High Compresses both static and dynamic pages.
Low Compresses only static pages.
None No compression is used.
Given the k... |
I'm using the 3/2/1 network segmentation model from the open pci dss scoping toolkit and I'm running into a bit of a mental roadblock. I have a phone system (Mitel 5000 series, if it matters) that is on my segmented internal network.
The phone system appears to be firewalled. nmap shows only standard web and SSH manag... |
Hash.Type....: descrypt, DES(Unix), Traditional DES
Speed.GPU.#1.: 6215.8k/s
Hash.Type....: SHA-3(Keccak)
Speed.GPU.#1.: 20514.1k/s
see: http://hashcat.net/forum/archive/index.php?thread-2085.html
It looks like you can make attempts crack SHA-3 (keccak) 3 times faster than DES.
While Keccak is known as a very strong cr... |
BREACH, a new attack on SSL that targets HTTP compression, has recently been publicly announced.
I manage a few web servers. How can I audit them to check which of them are potentially vulnerable to BREACH? Is there a simple way to scan a web server to check this?
(The emerging advice for how to defend against BREACH... |
There is a lot of tools out there to do a lot of things with, like sniffing, scanning, and even backdoors. However, I have a really hard time trusting these tools. When I install them at home and target my computers, how can I trust that the tools I'm using do not harm me?
Example 1 - Metasploit, Meterpreter especial... |
...I am really annoyed and unsettled by the password reset email I just received from Microsoft.
What should I think of this? My email client correctly told me that the underlying url is not the same as advertised...
I prepared a nice screenshot but can't post it because of missing reputation...
The text of the email i... |
Do they offer any benefits at all to the security of key distribution?
|
I have some tasks that go like so:
Spin up some new EC2 instances (Amazon Web Services)
Get them to execute a task
Kill them
The problem is that they're (seemingly) randomly assigned an IP address, and by chance a new machine reused an address that had previously been used.
This obviously lead to the following error,... |
I am currently working on an app that needs to create GPG key pairs using the gpg tool. Unfortunately, this tool takes a long time to generate a key pair if there is insufficient entropy/randomness available on the system to do so. A common workaround for this is to install the rng-tools package as it is called on Debi... |
I saw various different scripts for a buffer overflow attack. Many of the scripts include lines that look like this:
char code[] =
"\xdb\xd7\xd9\x74\x24\xf4\xb8\x79\xc4\x64\xb7\x33\xc9\xb1\x38"
"\x5d\x83\xc5\x04\x31\x45\x13\x03\x3c\xd7\x86\x42\x42\x3f\xcf"
This one is from the CastRipper [.m3u] 2.9.6 stack buffer over... |
I am working on an SEH exploit. the problem I am facing here that all POP/POP/RETN addresses end with null bytes, so everything placed after it gets corrupted.
Is it possible to use Metasploit Msfencode to encode the address of the POP/POP/RETN instructions its self to get over the problem of the null byte ?
The exploi... |
I have an address (i.e. 0x010f73fc) and I need to know where this address exist ? is it on stack or heap ?
In another way, how to differentiate between addresses that belong to the stack and addresses that belong to heap ?
|
I would like to implement a REST API with Basic Authentication which relies on username and password. Because REST is stateless the user would have to reenter username and password for every request without storing them in a cookie. As storing username and password in a cookie is not an option another solution is neede... |
I want to learn how to detect and write exploits for the Android OS. I am a bit familiar with Linux and have some knowledge in scripting in ruby and python. I had learnt how to write Exploits for basic buffer overflows and SEH. However I am finding very little material for finding and writing Android Exploits. Any idea... |
This is a security system that I would like to know the name of, here is a description:
I have heard that some people will use a separate computer for decrypting messages. When they revive a message they will put it on a thumb drive and then they will carry it to a separate computer that is not connected to the intern... |
Is it possible to make a program which uses client certificate authentication with only public and private key (I have not generated any certificate, I have only public and private key).
Simply, I want to make authentication on server with client certificate authentication. But it is hard to make client certificate pro... |
As a forum administrator, how can I find a client's real IP address? Are there any third party tools or weakness that expose the real IP address?
|
With regard to these three items
Certificate Authorities (CA)
Gateway certificates
End-point Certificates (client-cert)
What is the significance of the Common Name CN with regard to the a VPN? Does the Certificate Authority have to have the CN of the Gateway Cert? Any other information about the CN with relation to V... |
For the purposes of creating a VPN, I can't find a logical explanation of OpenSSL's/x509 scheme. I'm royally confused about these three terms,
Certificate Authorities
Gateway certificates
End-point Certificates.
I've read both Openswan: Building and Integrating Virtual Private Networks, and Building Linux Virtual Pri... |
I have a host that is NAT'ed and I have opened a single port in my router so the host is reachable by the external world. I tested if it was reachable by running a service and connecting to it externally.
I stopped the service, but the port is still open on the router. When I run nmap from an external server, it doesn'... |
Is formatting a device before encrypting more secure as opposed to encrypting the device without a formatting?
|
I need to know if the applications (contained in the blackberry store) are verified by blackberry before exposing them for downloads in the store.
|
Can someone explain to me the relationship between FISMA and OMB Circular A-130?
|
I was wondering how to encrypt by doing a AES-Twofish-Serpent encryption. Does this mean I encrypt in AES first then after that in Twofish, and after that in Serpent (three separate encryptions). In truecrypt they talk about cascading in xts mode, but I was having trouble finding a tutorial on how to do it.
|
Is it better to create a separate SSH key for each host and user or just using the id_rsa key for all hosts to authenticate? Could one id_rsa be malpractice for the privacy/anonymity policies?
having one ssh-key for all hosts:
~/.ssh/id_rsa
~/.ssh/id_rsa.pub
in comparison to separate ssh-keys:
~/.ssh/user1_host1
~/.ss... |
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