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According to process of authenticating a server certificate: What's keeping a malicious server to fill up a valid server certificate since it knows all the things: Forged Server public key (man in the middle public key instead of actual server public key) Certificate serial number. (actual server) certificate validity period (actual server) Server's DN (actual server ... but we are sitting in the middle of the IP route) Isser's DN Issuer's Digital Signaure This question is similar to (How does an SSL server prove its identity?) which deals with step 4, but I am interested in step 3
I have 3 CentOS server configured for my applications. Recently I recognized that there is so many attacks to my servers. I have so many logs about attempt to login to my servers using sshd from unknown IPs. This is some part of my secure log: May 25 03:45:03 mail sshd[22291]: Invalid user user from 42.121.117.150 May 25 03:45:03 mail sshd[22303]: input_userauth_request: invalid user user May 25 03:45:03 mail sshd[22291]: pam_unix(sshd:auth): check pass; user unknown May 25 03:45:03 mail sshd[22291]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=42.121.117.150 May 25 03:45:03 mail sshd[22291]: pam_succeed_if(sshd:auth): error retrieving information about user user May 25 03:45:05 mail sshd[22291]: Failed password for invalid user user from 42.121.117.150 port 59430 ssh2 May 25 03:45:05 mail sshd[22303]: Received disconnect from 42.121.117.150: 11: Bye Bye May 25 03:45:07 mail sshd[22563]: Invalid user user from 42.121.117.150 May 25 03:45:07 mail sshd[22564]: input_userauth_request: invalid user user May 25 03:45:07 mail sshd[22563]: pam_unix(sshd:auth): check pass; user unknown May 25 03:45:07 mail sshd[22563]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=42.121.117.150 May 25 03:45:07 mail sshd[22563]: pam_succeed_if(sshd:auth): error retrieving information about user user May 25 03:45:09 mail sshd[22563]: Failed password for invalid user user from 42.121.117.150 port 59655 ssh2 May 25 03:45:09 mail sshd[22564]: Received disconnect from 42.121.117.150: 11: Bye Bye May 25 03:45:11 mail sshd[22565]: Invalid user user1 from 42.121.117.150 May 25 03:45:11 mail sshd[22566]: input_userauth_request: invalid user user1 May 25 03:45:11 mail sshd[22565]: pam_unix(sshd:auth): check pass; user unknown May 25 03:45:11 mail sshd[22565]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=42.121.117.150 May 25 03:45:11 mail sshd[22565]: pam_succeed_if(sshd:auth): error retrieving information about user user1 May 25 03:45:13 mail sshd[22565]: Failed password for invalid user user1 from 42.121.117.150 port 59861 ssh2 May 25 03:45:13 mail sshd[22566]: Received disconnect from 42.121.117.150: 11: Bye Bye May 25 03:45:15 mail sshd[22570]: Invalid user user from 42.121.117.150 May 25 03:45:15 mail sshd[22571]: input_userauth_request: invalid user user May 25 03:45:15 mail sshd[22570]: pam_unix(sshd:auth): check pass; user unknown May 25 03:45:15 mail sshd[22570]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=42.121.117.150 May 25 03:45:15 mail sshd[22570]: pam_succeed_if(sshd:auth): error retrieving information about user user May 25 03:45:17 mail sshd[22570]: Failed password for invalid user user from 42.121.117.150 port 60107 ssh2 ... May 30 05:28:20 mail sshd[29998]: Failed password for root from 219.138.135.68 port 45105 ssh2 May 30 05:28:21 mail sshd[30273]: Failed password for root from 219.138.135.68 port 53227 ssh2 May 30 05:28:21 mail sshd[30266]: Failed password for root from 219.138.135.68 port 51786 ssh2 May 30 05:28:21 mail unix_chkpwd[30296]: password check failed for user (root) May 30 05:28:21 mail unix_chkpwd[30297]: password check failed for user (root) May 30 05:28:21 mail sshd[30280]: Failed password for root from 219.138.135.68 port 55313 ssh2 May 30 05:28:22 mail unix_chkpwd[30298]: password check failed for user (root) ... May 31 11:12:38 mail sshd[2461]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=211.233.60.37 user=root May 31 11:12:40 mail sshd[2461]: Failed password for root from 211.233.60.37 port 48375 ssh2 May 31 11:12:40 mail sshd[2462]: Received disconnect from 211.233.60.37: 11: Bye Bye May 31 11:12:45 mail unix_chkpwd[2671]: password check failed for user (root) May 31 11:12:45 mail sshd[2669]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=211.233.60.37 user=root May 31 11:12:47 mail sshd[2669]: Failed password for root from 211.233.60.37 port 48619 ssh2 May 31 11:12:47 mail sshd[2670]: Received disconnect from 211.233.60.37: 11: Bye Bye May 31 11:12:50 mail unix_chkpwd[2675]: password check failed for user (root) May 31 11:12:50 mail sshd[2673]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=211.233.60.37 user=root May 31 11:12:52 mail sshd[2673]: Failed password for root from 211.233.60.37 port 48905 ssh2 May 31 11:12:53 mail sshd[2674]: Received disconnect from 211.233.60.37: 11: Bye Bye ... How can I block this kind of attacks to my server? I have iptables installed on my server and all ports (except my needs) are rejected inside it.
I already know that some concerns of lack of security in TCP/IP are that TCP/IP does not support strong authentication of packets and no encryption of packets. What other weaknesses are there in the TCP/IP regarding security concerns?
The enterprise where I work has a proxy server that traces and filters our web activities. Employees claim that they can know the links that we visited and see the content of HTTP web sites, but they can't see the content of HTTPS secured web sites because the content would be encrypted by the server. I don't share the same idea and I think that there are plenty of ways to access the HTTPS content. Could someone give me some type of attacks that could let them access the content of our HTTPS secured navigation or hijack our sessions? Just guessing: One of the things that could increase the risk that they can execute a MITM attack as the image shows is the fact that they give a preinstalled Windows XP/7 system to new employees so they can install malicious certificates to these computers and make them trust additional Certification authorities
If I do not define any range (or if the range is large like a hundreds of ports), Nmap is returning ports as opened. However, if I put a smaller range or just scan a specific port, it says it's closed. For example: nmap -sV 1110/tcp open nfsd-status? 1111/tcp open lmsocialserver? 1112/tcp open msql? 1113/tcp open ltp-deepspace? 1117/tcp open ardus-mtrns? 1119/tcp open bnetgame? nmap -sV -p 1110-1120 1110/tcp closed nfsd-status 1111/tcp closed lmsocialserver 1112/tcp closed msql 1113/tcp closed ltp-deepspace 1114/tcp closed mini-sql 1115/tcp closed unknown 1116/tcp closed ardus-cntl 1117/tcp closed ardus-mtrns 1118/tcp closed sacred 1119/tcp closed bnetgame 1120/tcp closed unknown
I recently discovered a way to bypass a commonly used security seal system, requiring no special equipment and taking only a matter of seconds. I feel obliged to disclose this, so as to avoid the possibility of users of that seal system harbouring a false sense of security. I would use CERT's Vulnerability Reporting Form, but that is only intended for software vulnerabilities. Is there an equivalent responsible disclosure system in place for the physical security industry?
I am an admin of an immigration forum. Security is my job One and protecting our members's info is my highest priority. Recently, I discover that there are 3 members who have posted from the same IP addresse and the same iPhone browser info. My questions, Is it possible that different people would have the same IP address for their iPhones? Can different people have the same iPhone plan would have the same IP address? I can find out the location of an IP address of the iPhone, but does that mean the owner resides at that location?
Say I have previously created a private/public key combination, and decided at the time to not protect the private key with a password. If I later decide to "beef up" security and use a password-protected private key instead, would I need to generate a new private/public key pair, or can I simply add a password to my existing private key? Is the opposite possible as well, can I "remove" a password from an existing private key?
I wish to set up SSL/TLS for my site. How can I do this on my own without using a certificate authority. The site will be accessed only via certain machines so I can easily install the public certificates on their browsers.
There is a web application which contains a search function. When I search for aaaaaaaaxss I get this: <meta property="the:property" content="100 Results for aaaaaaaaxss (Page 1)" /> It strips the < and > characters but not double quotes. However, since I cannot get rid of the other input, I cannot use 1;javascript:alert(1) or something similar. Is this filter secure?
I've been reading about SSL/TLS and I was surprised when I saw the amount SSL/TLS implementations that exist. wikipedia. So, is there really a need for all these different implementations? Wouldn't it be cheaper, more productive and faster just to mantain one implementation like OpenSSL?
I have two questions regarding Tor (onion routing). How do I receive responds from a server when I use onion routing, I've read that, the last node(exit node) will use the same path I used but in the reverse order, but that means that the last node will know who I am. It was never clear anywhere but I guess that the exit node(node 100) has saved only the node before it , only knows node99 , and node99 knows only node98 etc, but that still doesn't make any sense since if the exit node , knows only the node before it, it will encrypt only with the public key of the node before it, etc.. . So the communication is still not safe. Also question2 If I the website use SSL how will the onion routing work? If its like this me->encryption node1->encryption node2->...->encryption node100->website running SSL. Will I be the one to encrypt the connection from node100 to the website running SSL, or will node100 do that work? Meaning can node100 view the message I want to send the the website running the SSL and then encrypt the message with the public key of the website, or do I encrypt it the first place making impossible for node100 to view the message. And when the website responds , it will respond encrypting the message with the public key of node 100, right? Edit to reply to @Phillip [Me]=>Node[1]=>Node[2]...=Node[Exit]=>SSL-Site , exit node doesn't know the clear text cause I encrypted with the site's public key(SSL). SSL-Site=>(SSL encrypted with my public key)Node[Exit]=> Node[Exit-1]=>...=>[Me] How does the site know that the message should be encrypted with my public key, and If it does isnt it easy for an attacker to find out who am I(if he controls that SSL site), also how does Node[Exit] know how to send the response back to me? Is Node[Exit] a trusted node that can betray me or keep me anonymous, meaning all my anonymity depends on how trusted that node is?
Assumption used: all password that I've used have been salted with some random elements before hashed and stored somewhere in their database. If my previous password exists only as salted-hashes in their database,then when I: trying to use a previous password during the password reset phase (as I type it into the new password textfield), how did they know that I was using a previously used password? (side note: Please down vote this question if it is not really constructive or thought provoking,so I can take corresponding measures.)
I have an ASP.NET web application which uses HTTPS and XML based request-response. It seems a user's session cookie can be retrieved via XSS, if the request/response is intercepted and malicious JavaScript code is added as a payload. Since it is an XML based request-response, the payload has to be HTML encoded. Here is an example: "<iframe name="if(0){\u0061lert(1)}else{\u0061lert(document.cookie)}" onload="eval(name)"/> Is there any way I can stop executing any malicious script? How to identify a request/response containing a malicious script? I noticed that all malicious scripts must contain ", &, ( and ), but user data may also contain these characters. How do I stop such a script to be run on users' browsers? I have already tried decoding all request/ response to corrupt the script which works, but my requests/responses contain user data which contains characters like &. This leads to the whole XML to become corrupt, which crashes the application.
I have been looking for an operational security guide for generating one's asymmetric key pair for (Open)PGP. I have found plenty of technical guides for how to use GnuPG to generate RSA key-pairs, for example, but not much organized content of how to do so securely. The use case is an average user wishing to use asymmetric encryption for signing, encrypting, and decrypting email and other file types. The threat model for creating the key pair does not include having to fend off three-letter agencies, organized crime, terrorists, or malicious corporations (i.e., there doesn't need to be a step regarding hiring body-guards or getting 24/7 security systems). I've gleaned from various sources online (including the very helpful GnuPG mailing list & documentation, the Debian Wiki, RiseUp.net, and this guide) the following steps as a general guide, but I am not sure if I am missing something. What else does one need to consider in this scenario? Find a computer that you think is relatively free of malware Download a Live Linux distro CD/DVD/USB, and verify its signatures to make sure you are not installing a tainted version Launch the verified Linux distro Make sure the distro is completely disconnected from any network connection before proceeding Configure GnuPG by editing the .gnupg/gpg.conf file to follow the guidelines here Use GnuPG to create private RSA key, and two subkeys (signing & encrypting) Set expiration date on (public) sub-key Create both a paper and digital backup of master private key Store the backups in two different physical locations, so no single point of failure Create a revocation certificate for the private master key Create both a paper and digital backup of the revocation certificate Store the backups in two different physical locations, so no single point of failure Strip the master private key from the keychain Copy over GnuPG keychain without master private key to work computer, personal laptop, etc.
I am doing an HMAC of some cipher-text, IV and encryption algorithm. Right now I am using a hard-coded key that is known to both sender and receiver. I was wondering if the key should be changed once in a while? If it does, how would I synchronize the keys with the receiver? Is sending the HMAC key in plain-text a very bad idea?
If I was able to view any page on a website as localhost using SSRF, what files should I check for? I checked to see if I could view robots.txt normally, and I couldn't, but using SSRF, I was able to. What other files are typical on websites that are normally hidden to the public, but would be visible on the localhost?
How can I block websites in Firefox from viewing my browsing history within my browser cache? For example; I've done some Google searches that Amazon is now starting to use to target advertise; the issue here is that Amazon is able to view my history for Google; how can I prevent this at the browser level?
It is asked in stackoverflow, but I suppose maybe it is more suitable to ask here. It is said that openssl are widely used, however, as far as I know, the most popular browsers seem not use openssl, instead, they use other SSL libraries like: NSS (for all firefox and chrome in Linux) SChannel (for browsers in Windows) Secure Transport (for browsers in Mac OS X). Am I right? Or is there any concept I'm taking wrong? Thanks.
Wordfence reports the following visitor: An unknown location at IP 0.0.0.0 visited 4 hours 45 mins ago IP: 0.0.0.0 Browser: Baiduspider version 2.0 Mozilla/5.0 (compatible; Baiduspider/2.0; +http://www.baidu.com/search/spider.html) An unknown location at IP 0.0.0.0 visited 4 hours 45 mins ago IP: 0.0.0.0 Browser: Opera version 12.15 running on Win7 Opera/9.80 (Windows NT 6.1; WOW64) Presto/2.12.388 Version/12.15
This is something which I have been wondering and trying to find an answer for, but yet to come even remotely to one. Why do you need a 4096-bit DSA/El-Gamal key when AES uses only 256-bit keys?
I've lost my master password. Not all is lost as I know the original word that generated the password: It was generated by a random case switching for consonants and random vocal to numbers. For instance: a and A become 4. I'm searching online for list generators that takes the seed word and generates permutations as I've described. I yet have to find a solution. Does someone know a generator that matches my requirement, or do I have no other option than to make my own word list?
One of my friends told me that running tor in a virtual machine Linux and then passing it through a proxy on the underlying Windows would provide in his words great security. Is this true?
I have set up an SSH server to accept only login using codes generated by Google Authenticator (I have disabled all other forms of authentication on that port). After having rebooted my remote machine, it keeps giving me the Access Denied error after having entered the code on the authenticator app. It has been working flawlessly up till now (i.e. before the reboot). So far, I've logged in using a scratch code (which it accepts), and have tried generating a new secret and scanning this new QR code with the Google Authenticator app and testing it using another terminal, all to no avail. I have also tried deleting the libpam-google-authenticator module and reinstalling it, generating another code and trying to login again from another terminal. This also didn't work. What could possibly be going wrong?
Given that an attacker only knows the public key and cipher text, why is it difficult to decrpyt the message ? If the knows the N value will he be able to decrypt it ?
By several REST clients the credentials are sent with every request through custom HTTP authorization headers to the REST service. Is there a way to force file download in the browser when accessing files stored in the REST service, is protected with this kind of authentication? Force file download: Content-Disposition: attachment. Force file download in browser: document.location.href="{downloadURL}". There is no way to force file download with XHR. REST requests must be stateless (according to the statelessness constraint of REST), so the session must be maintained by the REST client, and that's why I have to send credentials with every request.
There are well known attacks to WPA by capturing handshake and running offline hashcracking against it. Also there are tools to exploit vulnerability in WPS to get the PIN. My question is why WPS handshake (if it is called handshake) cannot be captured and the PIN revealed. It seems impossible otherwise obviously someone had done it already.
Did anyone successfully exploit CVE-2010-4478 in the past? This is insufficient validation of the J-PAKE public key parameters in OpenSSH up to 5.6. I'm dealing with a vulnerable machine running OpenSSH 5.1 p1. I need to get a flag but in order to do so, first I need access to the server. I found the vulnerability of jpake, but I've been trying to exploit it with no luck. I downloaded the code from https://github.com/seb-m/jpake/tree/master/openssh-jpake then downloaded a OpenSSH client v5.1 p1, replaced the files downloaded from github and ran make. The code won't compile unless I comment lines 156-159 and 1316-1317 in sshconnect2.c. I don't think those lines are relevant but when I try to use the exploit as said in the readme, ./ssh -o "ZeroKnowledgePasswordAuthentication yes" user@host, I'm getting an error saying that this option doesn't exist, so I don't know whether it's due to comment those lines out or due to another thing. That's why I'm asking whether is there someone who have successfully exploited this vulnerability in the past, and can throw some ideas about why it's not working. Also, if you know any other way to bypass the authentication of this version of OpenSSH, it is very welcome. edit: I already got access to the server by another mean, but I'm keeping this question opened to see whether or not someone has something to say about it.
I need some help in understanding the security risks if I want to use OAuth 2.0 (Facebook, Twitter and G+) as standard login provider for an E-Commerce site. Keeping in mind that I will not be saving Credit Card information on the site or in any of the data stores. I would be utilising services such as PayPal (And Similar Services)/EFT to achieve payment methods. I had a quick glance at this documentation for standard security assessments. But still no where closer to understand if the OAuth 2.0 would be a viable authentication option. Any advice would be great. I have the Same question posted on Stackoverflow
My boss proposed me to code from home on the their machines via internet, in two possible ways: I would connect to their computer and work on their machine, as if I was in front of the computer(from what he said the method used in this case would not be a VNC but something different) Via SVN My concern is all about the privacy for the first way. It is easier, I'm not a security expert and I would be not so happy if he could sniff network coming out of my router. In this case he could see the traffic of all my family, and this is very annoying. Could someone give me some tips to understand if this way of working could be dangerous for my privacy or not? What should I pay attention to?
I've bought a new phone, where one of its products can be activated by receiving a phone call. If someone uses a spoofed SIM card - with a number I recognize - I'll likely answer the call. Are there ways to circumvent this? I'm currently using a phone for data only, and another for calls and SMS: This leaves my calls and texts subject to eavesdropping. Would reinstalling the phone's OS weekly be a solution? Perhaps there's another way?
Google recommends using a 130-bit cryptographically-secure random number as an anti-forgery token. Why do we need so many bits? If an attacker decides to mount a brute-force attack, wouldn't you be able to detect and lock them out after a few attempts? With as little as 30-bits, you've got 1 million possible tokens for 1000 concurrent users. Guessing the token using brute force seems extremely unlikely. My point is that 30-40 bits of data seems very hard to break using brute force. So why does Google recommend 130-bits? Isn't that just overkill? UPDATE: Okay, say you couldn't prevent a brute force attack... According to this Quora post Facebook gets 500,000 unique visitors per minute. Assuming each user makes one request per second, you've got one request per 2 microseconds. Therefore, we can safely assume that (as of today) the most powerful attacker will be capable of sending at most one request per 2 microseconds. Next, assume that we expire tokens after 5 minutes. This means that an attacker can fire 1.5108 requests before the token expires. Next, assume we want the attacker to have less than a 1% chance of guessing the token. Therefore we need a pool of 1.51010 tokens per active token. So if you have 500,000 concurrent users (Facebook) you need 7.5*1015 tokens (one pool per user). This means you need 53 bits of data, which again is nowhere near the 130 bits which Google is asking for.
Note: Original question asked at https://stackoverflow.com/questions/24012390/is-this-token-based-web-service-secure but here seems to be the right place for it. The company that I current work for has an internal application, it provides some RESTful (sort of, just a collection of URLs) APIs. To access the APIs outside of the company network would require an HTTPS connection and a token (if accessing within the company network, no restriction is applied). To call an API, the caller (another internal application or employee) will need to create a token by something like this: Sort the URL parameters Hash part of the sorted URL with a salt (global constant) Use a substring of the hash as the token Append that token as a parameter in the URL and send the request The server will perform the same algorithm on the original URL, if the token comes out the same, the request is considered authenticated. I am no security expert, but this feels wrong to me, but I can't fully explain why. So I'm asking for help from the security experts, what are problems you see here? Or am I being too paranoid? Thanks.
Apple has just announced iOS 8. The new version appears to be more extensible than previous versions, and one of the new possiblities is to allow developers to develop custom keyboards, different than the system's default. Android has had this feature for quite some time. On Android, those keyboards are known as a possible security threat, most notably by acting as a keylogger. Does iOS 8 prevent such malicious behaviour from happening? If so, what security mechanisms are in place?
I'm developing a personal project and one part of the project is a php website, hosted at hostinger as a free plan, that allow clients to ping to it and stores the WAN IP and the NAT IP of them. They can ping to the web page just making a GET request to: mywebsite/ping.php?ip=XXX.XXX.XXX.XXX&description=USERNAME where 'ip' is the NAT IP and 'description' is a parameter to store the name of the user. // Snippet of ping.php // obs.: didn't handled the inputs in a correct way because I'm just testing $real_ip = $_SERVER ['REMOTE_ADDR']; $ip = isset($_GET ['ip']) ? $_GET ['ip'] : ''; $description = isset($_GET ['description']) ? $_GET ['description'] : ''; if (!empty($ip)) { // If ip is not set or empty, do not save anything // saves the ip (nat), description and the real ip into database } else { // do nothing } My website is up and running. I tested it and it saves my real and local ip. I also created a php file to see a list of all clients that ping the server. The mistery I deployed the website online yesterday and made some tests pinging to it. It stored my IP ok. Today I stopped working on it a little bit and when I was back I realized that 10 different IPs pinged my ping.php file with the 'ip' parameter set to their local NAT IP. See the IP's list here During the time that I was off I'm sure that none of my client programs pinged to the file since my PC was shutdown. Also the IPs found (real IP, not NAT) were all different from mine (mine didn't change until the time I checked the ghost IPs). Question: How is that possible someone reach a php file on web and make a request using the righ parameters since just me and god knows about the existence of this php file on my web server? Additional information In my .htaccess located in htm_public, I disabled the indexing. Nobody but me accessed my hostinger account There is no index or default page on my web server, just the ping.php and show_all_ips.php I tried some Google dorks to find my ping.php file but couldn't find anything
If there is an employee uses the internet through an internal proxy in his company, and he use a paid VPN service to browse safely, can IT side be able to monitor his behavior?
I have been reading about SpyProxy. Can someone explain me this phrase I found in the article ? Here it is: We monitor the guest OS and browser through “triggers” installed to look for sandbox violations. I am looking to understand what is the nature of the triggers they may install in the Virtual Machine ? I appreciate any help/indication.
I've been wondering about this scenario for a while but I cannot fully understand how it works. Say I am sitting in a cafe on my laptop with wireshark, the cafe has an open WiFi connection. Is it possible for my laptop to become a wireless access point (i will call it something similar to the cafe router) but then redirect all traffic going through my laptop to the actual cafe router as my router is not connected to the internet. This may help: Normal route: users ---> Cafe AP ---> Internet What I want to do: users ---> Fake AP ---> Cafe AP ----> Internet The part I am confused on is how to make my fake AP redirect all traffic to the cafe AP. Thinking about it, is it possible to connect to the Cafe AP and simply sniff in promiscuous mode to receive packets from all who are connected?
After reading about BitCoins, I can't help but contemplate the idea of the a government withdrawing paper money and bringing all currency transactions digital, via a bitcoin-like method where every unit (1 cent, US, for example) has an id and an owner. This would theoretically help eliminate theft, tax evasion, money laundering, etc. What I want to know is: I've read articles about the capabilities of some extremely powerful mafia-style cyber criminals that can basically break into anything. Is an entity such as a government capable of maintaining the security of such a system?
I know that hashing is a one way function and encrypted messages could be retrieved if you know the corresponding key to which you encrypted the message. Other than the ability to retrieve, what advantages/disadvantages are there in hashing over encryption?
Now, I understand this might not be the right place to post about Acunetix but I'm searching my site for any exploits and a couple of SQL Injection exploits have shown up on a /Profile page, how would I be able to see the issue through my own browser (i.e. See the SQL error through my own browser instead of the Acunetix browser.) Request Data bf=2&fm=1%27%22&os=1&update=Save&user=%7busername%7d
What are the security implications of executing external processes using Java ProcessBuilder/Process? For example: Runtime rt = Runtime.getRuntime(); Process proc = rt.exec("processExecutable"); InputStream is = proc.getInputStream(); int c; while ((c = is.read()) != -1) { System.out.print((char) c); } int exitVal = proc.waitFor(); From what I understood, communication between Java and external processes is via pipes, so I am interested how difficult it is for someone to eavesdrop and get data sent from a process back to Java on Unix? Will only users logged in to the same machine have the potential to eavesdrop? Will any logged user have the potential or only administrators or users in the same group etc. as user running the Java app which executed the external process?
I'm a little bit confused about the contents of Finished Message used during Handshake Protocol. In particular, this message (clientside) contains the connection-id originally sent from the server and it also contains a hash value derived from all previous handshake message and master secret. So this message is encrypted with a key derived from master secret or only connection-id is encrypted, and Finish Message is still transmitted in plain? Another question is about detecting replay attack serverside. The server receives Finished Message from client; how can server correctly detect a replay attack from Finished Message and why we use connection-id and hash only one isn't enough?
I see a lot of materials in Internet about this technique. I'm not really interested in malwares, but I'm curious when you change bytes to an exe with other bytes, wouldn't this corrupt the exe? I can give example videos if somebody didn't understand my question.
The AES algorithm and asymmetric encryption use multiple key lengths that affect the strength on the key used. But, how does the key size and algorithm strength affect encryption strength?
i'm a newbie and i'm having a problem that i can't find it by google. I'm researching abbout DDoS detecting method now. As we can see that nowadays people often analyze networking traffic from router by a computer inside LAN. But i see that there're some companies which have services for traffic monitoring and packet information capturing. I wonder how they can do it. Do they have to configure their own customer's router for the information or do something elso. Also, can i config a router for directing its traffic to a cloud outside its network? Thanks in advance :-)
From Beginning Cryptography with Java - chapter 4, digital signatures: Signatures are created using the RSA algorithm by applying the RSA algorithm using the private key and then distributing the result as the signature. Because of the way the RSA algorithm works, this means the signature can be decrypted using the public key, giving you the process you see in Figure 4-5. The reason it works so well is that if a signature decrypts successfully with a given public key, then it must have been created with the corresponding private key. "the signature can be decrypted using the public key"? I thought decryption is done by the private key...?
Consider a user who wants to use a password manager for their banking passwords. Advice from banks usually says they should never write down their password. The user would be concerned about going against that advice, as it could mean their bank would refuse to accept liability for any fraud that may occur on their account. So, can they use a password manager? Does storing the password encrypted count as writing it down? This is a legal and policy question; I am already aware of the technical risks and benefits of using a password manager. Answers may be country specific (and even bank specific). I'm in the UK but I am interested in answers from anywhere in the world.
Consider the problem of hardening an existing, database-backed web application, to detect attacks and stop them where possible. It seems like one plausible approach might be to build an intrusion detection system that has observability at two points: (a) at the web server level (e.g., to observe the page being executed, the request URL, request parameters, the session cookie), and (b) at the database level (e.g., to observe the SQL query that is being executed). I can imagine many opportunities to build an anomaly detector and monitoring system that can detect many attacks. For instance, if in the past SQL queries initiated from the page foo.php have been SELECT queries, and now you see an UPDATE or DROP command, that might be suspicious. If I see a query that contains a semicolon or a nested subquery, and I've never seen that before from that page, that might be suspicious. And so on. This is the kind of thing that can only be be implemented with visibility into both the web request (e.g., at the web server or front-end level) and the database. Has anyone looked at this kind of system before? Has anyone built it, and if so, how well does it work? Is there a standard name for this sort of system? (My understanding is that a web application firewall normally has visibility only into the web application but not into the database, so it is different.) Are there existing systems like this available commercially or as open source?
Are heap spray exploits possible, if the process we're attacking is a 64-bit process? Naively, it seems like the 64-bit address makes it difficult to mount a heap spray: to fill all (or a significant fraction) of virtual memory, you'd need to spray an absolutely ridiculous amount of data into the heap. I realize that on 64-bit platforms, the virtual memory address space is really 48 bits, not 64 bits, but that still seems to be more than enough to make filling the entire virtual address space unlikely. Therefore, naively, it seems like we might not need to worry about heap spray attacks against 64-bit processes. But is this conclusion correct? Are there clever ways of doing a heap spray even against a 64-bit process? (Assume that the target process is using ASLR, as is standard these days.)
In SSL/TLS handshake, a nonce is always sent by the client to server and vice versa. The nonce basically consists of a random number and unix timestamp. Why do we need the unix timestamp? As the nonce is always a random number, how does this protect from replay attack by a man-in-the-middle? Being a random thing, same nonce might be repeated in another handshake with the same server. Can somebody tell me any other purpose of this nonce?
So the first reason we give to encrypt content is to prevent against a man in the middle sniffing all data. That is the reason ssh is used and not telnet for example. But in today's networks where there are really no hubs and all switches how easy and how prevalent are packet sniffing attacks? What exactly needs to be done to get into a situation to sniff data and are there any tools to help? I am not saying anything about encryption here, its purely a question about the feasibility and/or practicability of packet sniffing attacks. In fact recording encrypted communications might be useful in some scenarios e.g. to do cryptanalysis on the data or other attacks. So how do I sniff data in today's networks?
Are there cases where a serious drive-by download attack could crash the operating system or the browser ?
How safe is a hybrid mobile application developed using a GET Web service over HTTPS? What are the pros and cons of using it and how safe is POST over HTTPS?
My office has about 20 PCs running Windows XP. I got a message saying that Microsoft is no longer releasing any security patches for Windows XP. However, we find that XP is very convenient for our work. Please suggest some possible ways to keep Using Windows XP for my PCs without any risk.
We have a long-standing ActiveSync device policy that requires an unlock code for all phones that use corporate email. It seems that iPhones with "swipe to unlock" and Android phones with similar technology process this policy different: iPhones allow a swipe to unlock feature, while Android does not. Is "swipe to unlock" just as secure as a pin code? Is the iPhone swipe to unlock hardware / software "better" than Android's comparable feature? Can the Android thumbprint unlock be enabled by the end user / administratively enabled? Can we disable the thumbprint on iPhones?
I'm implementing a way for users to share messages with other users. All users and admin-users have a unique key pair. A message can be sent from one user to multiple users. Admin-users, who always have access to all messages, in case a user loses his password, and then makes a new password (with a forgot-password email link), the admin-user can decrypt the message with the admin-user private key and encrypt it with the users new public key. Is there a way to automate this process, securely of course? I was thinking sending a mail to a local-server (not connected to the webserver), so the local server can login to the site as admin-user and give the user access, when they changed their passwords.
I have a classic ModSecurity configuration (apt-get...) SecRuleEngine Off SecPcreMatchLimit 1000 SecPcreMatchLimitRecursion 1000 SecAction "phase:1,t:none,nolog,pass, \ setvar:'tx.allowed_methods=GET HEAD POST OPTIONS', \ setvar:'tx.allowed_request_content_type=application/x-www-form-urlencoded multipart/form-data text/xml application/xml application/x-amf', \ setvar:'tx.allowed_http_versions=HTTP/0.9 HTTP/1.0 HTTP/1.1', \ setvar:'tx.restricted_extensions=.asa/ .asax/ .ascx/ .axd/ .backup/ .bak/ .bat/ .cdx/ .cer/ .cfg/ .cmd/ .com/ .config/ .conf/ .cs/ .csproj/ .csr/ .dat/ .db/ .dbf/ .dll/ .dos/ .htr/ .htw/ .ida/ .idc/ .idq/ .inc/ .ini/ .key/ .licx/ .lnk/ .log/ .mdb/ .old/ .pass/ .pdb/ .pol/ .printer/ .pwd/ .resources/ .resx/ .sql/ .sys/ .vb/ .vbs/ .vbproj/ .vsdisco/ .webinfo/ .xsd/ .xsx/', \ setvar:'tx.restricted_headers=/Proxy-Connection/ /Lock-Token/ /Content-Range/ /Translate/ /via/ /if/'" And I get this error: --70244300-A-- [04/Jun/2014:17:14:29 +0200] U4831X8AAAEAAFDVH5IAAAAS X.X.X.X 58274 Y.Y.Y.Y 80 --70244300-B-- GET /images/login_bg.jpg HTTP/1.1 Host: myHost.local User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:29.0) Gecko/20100101 Firefox/29.0 Accept: image/png,image/;q=0.8,/;q=0.5 Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate DNT: 1 Referer: http://myHost.local/css/main.css Cookie: symfony=9a09bb2c53df046aae0ed80c501c9585 Connection: keep-alive --70244300-F-- HTTP/1.1 200 OK Last-Modified: Wed, 05 Nov 2008 14:54:40 GMT Accept-Ranges: bytes Content-Length: 31429 Content-Type: image/jpeg X-Content-Type-Options: nosniff X-XSS-Protection: 1; mode=block X-Frame-Options: sameorigin Connection: close --70244300-E-- --70244300-H-- Message: Rule 7f36b7b712b0 [id "950901"][file "/etc/modsecurity/modsecurity_crs_41_sql_injection_attacks.conf"][line "77"] - Execution error - PCRE limits exceeded (-8): (null). Apache-Handler: proxy-server Stopwatch: 1401894869729902 23796 (- - -) Stopwatch2: 1401894869729902 23796; combined=9162, p1=144, p2=8864, p3=3, p4=82, p5=67, sr=0, sw=2, l=0, gc=0 Response-Body-Transformed: Dechunked Producer: ModSecurity for Apache/2.6.6 (http://www.modsecurity.org/). Server: Apache --70244300-Z-- The strange rule: # # -=[ SQL Tautologies ]=- # SecRule REQUEST_COOKIES\|REQUEST_COOKIES_NAMES\|REQUEST_FILENAME\|ARGS_NAMES\|ARGS\|XML:/ "(?i:([\s'\"`´’‘])?([\d\w]+)([\s'\"`´’‘])?(?:=\|<=>\|r?like\|sounds\s+like\|regexp)([\s'\"`´’‘])?\2\|([\s'\"`´’‘])?([\d\w]+)([\s'\"`´’‘])?(?:!=\|<=\|>=\|<>\|<\|>\|\^\|is\s+not\|not\s+like\|not\s+regexp)([\s'\"`´’‘])?(?!\6)([\d\w]+))" \ "phase:2, \ rev:'2.2.5', \ capture, \ multiMatch, \ t:none, \ t:urlDecodeUni, \ t:replaceComments, \ ctl:auditLogParts=+E, \ block, \ msg:'SQL Injection Attack', \ id:'950901', \ logdata:'%{TX.0}', \ severity:'2', \ tag:'WEB_ATTACK/SQL_INJECTION', \ tag:'WASCTC/WASC-19', \ tag:'OWASP_TOP_10/A1', \ tag:'OWASP_AppSensor/CIE1', \ tag:'PCI/6.5.2', \ setvar:'tx.msg=%{rule.msg}', \ setvar:tx.sql_injection_score=+%{tx.critical_anomaly_score}, \ setvar:tx.anomaly_score=+%{tx.critical_anomaly_score}, \ setvar:tx.%{rule.id}-WEB_ATTACK/SQL_INJECTION-%{matched_var_name}=%{tx.0}" I get this error for every request... Why !? EDIT: My SecRuleEngine is Off in my global settings BUT it's set to DetectionOnly foreach VHOST.
If someone is able to post on the forum of my website links to executable files (malware) hosted on remote websites: can we say that my website suffers from a security hole ?
If I click on the little lock icon in Chrome it says that the site in question is using TLS v1. I also checked using openssl and was able to hit the site using TLS1, SSL2 and SSL3. From what I understand SSL2 is not secure. Based on this, it appears that the site could be hit using any of the three. What determines the version of SSL/TLS that will be used when accessing a secure site from a web browser?
There are multiple gift card reseller sites that buy your gift cards and resell them at discounted price. I was wondering how these sites prevent sellers from reusing the pin and card number after it has been sold (you can use the pin and card numbers online, or even at the store without the physical card).
I am 17 years old and my ultimate job goal is a cyber security professional. I have been extensively studying TCP/IP, along with all other subjects in the CompTIA Network+ certification which I hope to obtain soon. I'm very familiar with tools such as OpenVAS, Wireshark, nmap, ect and I'm currently learning Python, and can write bash scripts. My question is what is what are jobs such as network security auditor or cyber security engineer like? and what things should be studied to start on this career path. Also just general information about working in the IT field would be welcomed.
According to https://www.owasp.org/index.php/Insufficient_Session-ID_Length: Assuming that the session identifiers are being generated using a good source of random numbers, we will estimate the number of bits of entropy in a session identifier to be half the total number of bits in the session identifier. How does one determine how many bits of entropy a particular implementation actually contains? For example, if I execute new BigInteger(130, new SecureRandom() under Java do I actually end up with 130 bits of entropy?
I've heard a TON of vague info on Gameover Zeus recently. One detail I can't seem to find is if it affects OSX? when I say I can't find it I mean from a credible source. I've found loads of people on forums saying the classic "Macs cant get viruses", but not any hard facts..
I really want to prove myself (to my parents) by winning a proper bug bounty How should I best prepare for this and go about actually finding bugs? Edit So can anyone give some web sites which I could read that would help me understand better how to win, and what free training materials are useful? I'm working through pentesterlab already. I've the looked up the most common vulnerabilities from OWASP things like XSS, SQL injection, PHP inclusion, CSRF, error disclosure. I've studied each of these and understand how they occur and how to demonstrate them. I've tried to audit many lines of source code from open source projects looking for parts that haven't properly escaped user input or other important things. I also tried to do black-box testing for things like XSS on staged sites (ones hosted separate from the in-use production server, for the purpose of testing) but nothing has really turned up. I've also read the public disclosure writeups of the bugs other people found. I understand that part of the problem is that there are people with years of experience who will find things first. And there are also people (like researchers) with much deeper knowledge in specific areas. But even so I think I should be able to make a positive contribution if I work hard, so I would appreciate any guidance
I'm wondering if anyone has previously proposed, evaluated, or deployed the following measure to harden systems against heap-based buffer overruns: basically, stack canaries, but applied before function pointers in objects stored in the heap rather than before return addresses stored in the stack. Consider a struct like struct whatever { int blah; char buf[256]; void (fp)(); // a function pointer } Notice that if there is an overrun that writes past the end of the buf field, it will be possible to overwrite the function pointer field fp. A compiler could plausibly defend against this by introducing a canary -- a secret random value -- stored between the buffer and the function pointer. Basically, the compiler would transform the layout of the structure to struct whatever { int blah; char buf[256]; unsigned int canary; // inserted by compiler; not exposed to source code void (fp)(); // a function pointer } For instance, the compiler could arrange to write the canary field with a global secret value any time the program writes to fp, and could check that the value of the canary remains unchanged any time the program reads from fp. This is basically the analog of stack canaries, but where now we focus on protecting function pointers in the heap instead of return addresses in the stack. It seems like a natural idea. Has anyone proposed this before? Has anyone prototyped it or evaluated the performance cost of doing something like this? Are there any non-obvious barriers to deployment (beyond the fact that it requires changes to compilers, just like stack canaries do)? Research I've done: I'm aware of the idea of inserting guard pages between objects in the heap, but that's different (it protects against heap overflows that go beyond the bounds of a single object, whereas I'm talking about something to protect against heap overflows that stay within the region of a single heap object). I'm familiar with Cruiser and ContraPolice, which places canaries between objects in the heap, but that too focuses on cross-object overflows rather than intra-object overflows. I'm also familiar with use of stack canaries or pointer encryption for protecting malloc's metadata, but again, that doesn't protect against intra-object overflows and is intended to protect malloc's metadata rather than function pointers.
Is it possible to write a snort rule that match on 2 different flows? For instance on a communication from host-a <--> host-b that happen at the same time as a communication on host-a <--> host-c ?
On my Linux machine (Alice), I am setting up a service account with an rsync cron job that will synchronise some files with a remote host (Bob). Obviously, I would want to make the rsync secure by using SSH with a keypair. So my question is: is there any point in passphrase-protecting the private key? If I passphrase-protect the private key, obviously I wouldn't put the passphrase in the cron job script. I would need to set up a persistent background ssh-agent process so that the cron job can use it. But then doesn't it somewhat defeat the purpose of the passphrase-protection? If someone can break into Alice, can't they just use the persistent ssh-agent to do all the bad things they need to? The only (slight) advantage, I believe, is that even if the intruder can copy the private key, they would not be able to use it elsewhere because they don't know the password.
I'm trying to set secure Trusted Platform Module (TPM) passwords on a network and would like to set it to the maximum length possible. How long can the TPM's password be? Is it limited by bits or by characters? Does anyone has information about this? EDIT: Yes, it's TPM 2.0 modules, embedded on Dell laptops and desktops mostly.It seems that it can be longer than 32 characters but I'm unsure about the (desired) max length. I'm thinking about using a random generator to set up the passwords. Right now I used the Windows' standard password generator for Bitlock. I do not know much about this, my idea was to set a very secure TPM (and seldom change it) and change the PIN of bitlock protection more frequently.
So pretty much all of the GNUTLS world is worrying about CVE-2014-3466. I checked my Kali and it responds with this - # apt-cache rdepends libgnutls26 \| grep -v lib Reverse Depends: telepathy-gabble qemu-kvm guile-gnutls gnutls-bin xxxterm xpp xfprint4 xfce4-mailwatch-plugin xen-utils-4.1 x11vnc wzdftpd-mod-tcl wzdftpd-mod-perl wzdftpd-back-pgsql wzdftpd-back-mysql wzdftpd wmbiff wget weechat-curses weechat-core webfs vpnc vlc-nox vino ucommon-utils totem-plugins telepathy-salut telepathy-gabble tdsodbc suricata sogo snort-pgsql snort-mysql snort slapd sipwitch-cgi sipwitch sipsak shishi-kdc shishi shisa scrollz samhain rtmpdump rsyslog-gnutls qpdfview qemu-system-x86 qemu-system-sparc qemu-system-ppc qemu-system-misc qemu-system-mips qemu-system-arm python-pycurl-dbg python-pycurl python-preludedb python-prelude python-mailutils python-gtk-vnc python-gnutls proxytunnel printer-driver-gutenprint prelude-manager prelude-lml postal pianobar passing-the-hash pacemaker openvas-scanner openvas-manager openvas-cli openvas-administrator nzbget nullmailer ntfs-3g ngircd newsbeuter network-manager netatalk nautilus-sendto-empathy mutt-patched mutt msmtp-gnome msmtp mpop-gnome mpop mozilla-gtk-vnc minbif mandos-client mailutils-pop3d mailutils-mh mailutils-imap4d mailutils-comsatd mailutils macopix-gtk2 lynx-cur linuxvnc lftp ldap-utils kildclient jd ircd-ratbox inspircd infinoted heartbeat gvncviewer gurlchecker guile-gnutls gtklp gtk-gnutella gsd gsasl greenbone-security-assistant gobby-0.5 gnutls-bin gnu-smalltalk gnomint gnome-settings-daemon gnome-control-center gkrellm ghostscript-cups freetds-bin filezilla exim4-daemon-light exim4-daemon-heavy empathy elinks-lite elinks ekg2-remote ekg2-jabber echoping dsyslog cups csync2 connman claws-mail-trayicon claws-mail-spamassassin claws-mail-smime-plugin claws-mail-pgpmime claws-mail-pgpinline claws-mail-bogofilter claws-mail charybdis centerim-utf8 centerim-fribidi centerim cairo-dock-mail-plug-in bitlbee ario aria2 anubis aiccu abiword There are a few POCs around - https://github.com/azet/CVE-2014-3466_PoC/blob/master/poc.py and http://radare.today/technical-analysis-of-the-gnutls-hello-vulnerability/. My question is other than launching the POC, how do I check for vulnerable machines? What if gnutls-cli is not present?
http://seclab.stanford.edu/websec/csrf/csrf.pdf points out that most CSRF protection mechanisms fail to protect login forms. As https://stackoverflow.com/a/15350123/14731 explains: The vulnerability plays out like this: The attacker creates a host account on the trusted domain The attacker forges a login request in the victim's browser with this host account's credentials The attacker tricks the victim into using the trusted site, where they may not notice they are logged in via the host account The attacker now has access to any data or metadata the victim "created" (intentionally or unintentionally) while their browser was logged in with the host account This attack has been successfully employed against Youtube. The authors of the paper went on to propose the addition of an "Origin" header but ran into resistance by W3C members: http://lists.w3.org/Archives/Public/public-web-security/2009Dec/0035.html To date, only Chrome and Safari implements the "Origin" header. IE and Firefox do not and it's not clear whether they ever will. With that in mind: what is the best way to protect against CSRF attacks on login forms? UPDATE: I am looking for a RESTful solution, so ideally I want to avoid storing server-side state per user. This is especially true for non-authenticated users. If it's impossible then obviously I will give up on this requirement.
I think I have a basic understanding of security concerns, but I feel like if I don't know everything, I'm going to implement lousy solutions. Below is my current strategy; Have I overlooked obvious best practices? I've read Can anyone provide references for implementing web application self password reset mechanisms properly? and think that I have the relevant parts covered. Flow An administrator triggers a password reset for a user in the system. The system locks out the user from the system, generates a 40 characters random alphanumeric string as a authtoken, and stores this hashed in the database with SHA1, together with the encrypted username, the time is was created and the hash of the old password. If the user have any previous authentication tokens in the db, it deletes them. The system sends a link to the email connected to the user having it's password triggered for resetting. The user clicks the link, which is over https, and the system reads the authtoken. The system hashes it again with SHA1, searches the database for it: The authtoken does not match: Error page. Please contact admin The authtoken was created more then 4 hours ago: Please contact admin The authtoken is found and active: Goto 6 The client gets presented a dialogue to select a new password and posts the new password with the same authtoken (in a hidden field) back to the server. The system checks again that the authToken exists, is active and that the password is not the same as the old one. If success, the system decrypts the username stored together with the authtoken, changes the password for this user to the new, unlocks the user, and removes the authToken from the database. The system redirects the user to the login page. So The only agent triggering the reset process is an authenticated administrator: No problem with maliciously locked-out users. All communication between client and server is going over HTTPS, with the possible and uncontrollable exception of the user's email solution. This is how the authToken is generated: const string authtokenAlphabet = abcdefghijklmnopqrstuvxyzABCDEFGHIJKLMNOPQRSTUVXYZ1234567890_-."; const int authtokenSize = 40; var authToken = string.Empty; while (authToken.Length < authtokenSize) authToken += authtokenAlphabet[_random.Next(0, authtokenAlphabet.Length - 1)]; Although I use the Random class, which is discouraged due to less than optimal randomness, would this really be a problem considering that only an an authorized and authenticated administrator can trigger the reset?
The media are currently (and have been) creating a huge ruckus surrounding the supposedly "undetectable" Gameover Zeus malware. The Daily Mail The Mirror The Independant PC World The Telegraph ...And a number of others. My question is... is there actually any increased risk to this particular malware, or are the media just running with it to run a scaremongering story? Are a combination of Malware Bytes and Microsoft Security Essentials sufficient for most users to be safe?
To log in to a enterprise web app, our security team is insisting on 2FA as it is hosted on our internal network. The proposed solution is to have a standard username (email address) and password login, which will then trigger a four digit PIN emailed to the user which they will have to enter to log in. To my mind that is two sides of the same coin (something the users knows) - using the email address, rather than sending the PIN to a phone number or a physical token. Is this strictly 2FA? Is it significantly more secure, or is it just an additional inconvenience to the user in return for little gain?
I want to understand the technical aspect of BitLocker and TPM, especially with Startup PIN. Does anyone know a technical survey report, preferred by a competent third party (not MS)? I have a few questions about this topic If I use the BitLocker StartUp PIN, do I use the TPM like a smart card? Like a smart card, can I change the maximal tries until the smart card resets? Or is there a other methode to prevent brute force? Can I retrieve my data at every point with the recovery key? (use hard drive on another pc, reseted TPM, ... ) In my bios a can chose between TPM 1.2 and Intel TPM 2.0, what is the difference? If leaving aside the transparency, can you say that BitLocker and TrueCrypt are equally safe? (IMHO transparency in TrueCrypt not really exist.)
If two persons use the same router, which has an embedded WiFi access point, for accessing the Internet, is it possible that one can see HTTP traffic HTTPS traffic TOR traffic of the other in the below mentioned scenarios? Both connect to the router via its WiFi access point. One connects to the router via its WiFi access point, the other via Ethernet. Both connect to the router via Ethernet. The router's WiFi access point uses the WPA or WPA2 protocol.
Suppose an attacker records all messages of a SSL handshake (RSA one-way), and starts a replay attack. When (after which message) can the server possibly detect the attack? Now suppose the attacker changes strategy, and sends the first three phases (up to the session key exchange), but sends this sequence many times. Why would an attacker do this, and what would be the impact on the server?
I'm designing a system where some combination of hardware and software (lets call it an appliance...) sends asynchronous secure archival to the cloud. By secure, I mean, AES-256 encrypted, with AES key and IV encrypted by RSA-2048 public key. There may be several such appliances, each with the same RSA public key. It doesn't matter. I want the decryption to occur when the user faces disaster and wants to get back her archives. By disaster, I mean, her computer may have been burned, or stolen, or she might have been forced to move quickly, something like that. In this case, I want something easy to use, easy to carry, easy to store. A USB key sounds great. But I don't want any malware able to read the private RSA key whenever this device is put inside a potentially unsafe computer. My guess is there should exist some commercially available solution, that do the following: Is factory written an RSA-2048 private key in my premises (not the vendor) Will never ever make the key visible over USB like would a plain RSA public key file on an USB thumb drive Will take encrypted data, decrypt it, and give it back decrypted Bonus points: Is Java compatible on at least Mac and Windows Takes configurable password to further protect the key (maybe...) does all I need in my protocol directly (AES key decryption, AES un ciphering...)
I'm working for a company that sells software products to customers some of which do not have the resources and/or know-how to build and maintain their own CA (used for the SSL communication of our software). In these cases we have to provide the certificates for them. The customers are completely independent and should NOT be able to communicate with each other, i.e. there should be no SSL trust between Customer I and Customer II. I have a rather general question about how to best built such a CA structure. These are the two variations that are currently considered. Company Root CA with SubCA for each customer: Root CA / \| \ / \| \ Customer I Customer II Customer III Independent (Root-)CA for each customer: Customer I Customer II Customer III What would be the pros and cons of each variant? Is there an established best practice for such a setup?
This is what facebook ships with their API php client: https://github.com/facebook/facebook-php-sdk-v4/blob/master/src/Facebook/fb_ca_chain_bundle.crt It contains dozens (hundreds?) Root CAs. But doesn't it make the client more prone to MitM attack? To clarify why I think: it's more chance that some of CA certificates will be compromised, than if they included a single certificate - the exact one they sign their certificates. Am I missing something?
I have a reflected XSS vulnerability in my Web application. I have decided to take the black-list approach instead of the popular white-list approach. My question is can there exist a malicious javascript call without opening parenthesis(\u0028) and close paranthesis(\u0029)? By malicious, I mean something that can impact the user. If your answer is YES, then please give an example code that can be injected into an XML.
Does CVE-2014-0195 (openSSL) affect HTTPS or only VPN tunnels? Reference: https://security-tracker.debian.org/tracker/DSA-2950-1, https://isc.sans.edu/
Given a proxy performing MITM SSL decryption and inspection, is it possible to install a wildcard certificate (*.domain.com) on the proxy signed by a root CA (such as VeriSign or GoDaddy) such that clients will not have to have a self-signed cert installed (since they will already trust the root CAs in their trusted store)? I'm thinking about this in terms of allowing BYOD devices on a network and avoiding the necessity of installing a cert on different device types such as iOS, Android, Windows Phone, etc.
I came across this link that dicusses how an attacker could exploit access control allow origin to get an anti-CSRF token: http://yossi-yakubov.blogspot.com/2011/09/bypassing-token-protection-against-csrf.html If the token in the above example was a one-use token (a new one is generated each time the page loads, and expires after use) how would that affect the results? Thanks!
In our web application, we allow customers to enter their bank account information as a method of payment (account number, routing number, bank name). This information goes nowhere at all; it's up to the client to process such payments using a separate system. What, if anything, should we be doing to secure this data? And where could I be looking to find information about this sort of thing?
I'm trying to get access into a Windows 2000 server through the vulnerability MS03_026. An exploit is provided by Metasploit but I don't know why it isn't working. After filling the options (basically the RHOST) and running it, it just says "Sending exploit" and return the prompt. Port 135 is wide open. Playing with payloads, only once it worked using a meterpreter/bind_tcp, but once connected, meterpreted didn't recognize any command (well, it did recognize help but didn't show anything). meterpreter > cd C: [-] Unknown command: cd. meterpreter > help meterpreter > pwd [-] Unknown command: pwd. Anyway, it's not working anymore, again with the "Sending exploit" and return to the prompt. This vulnerability is widely known, and all the resources I see shown it properly working, so I don't know what the hell may be happening here.
Microsoft deployed a patch for Windows 2012 R2 and Windows 8.1 that adds the following ciphers. Cipher suite Exchange Encryption Hash TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 DH AES SHA384 TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 DH AES SHA256 TLS_RSA_WITH_AES_256_GCM_SHA384 RSA AES SHA384 TLS_RSA_WITH_AES_128_GCM_SHA256 RSA AES SHA256 ECDHE is missing (note the first set of letters in the cipher name after TLS_). Grumblings about this lack of ECDHE support is also mentioned on the CERT forum thread Question Is there any TLS Survey that scans TLS cipher support in Websites for ECDHE? How widely supported is ECDHE in the client? Based on Microsoft's history, they might not prioritise ECDHE support until it's widely in use by servers, or web browsers. I hope to use this information to estimate if/when MSFT may include such support in SChannel. Aside: why do I want ECDHE? Because it's faster.
This article describes how to disable old versions of TLS, but in addition to doing so, "Multi-Protocol Unified Hello" is also disabled. # Disable Multi-Protocol Unified Hello md 'HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\Multi-Protocol Unified Hello\Server' -Force New-ItemProperty -path 'HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\Multi-Protocol Unified Hello\Server' -name Enabled -value 0 -PropertyType 'DWord' -Force I searched for that term, and didn't see anything besides other registry edits that disable this. What is the Multi-Protocol Hello, and why/when should someone disable/enable it?
Are there any tools or techniques that allow a scan of multiple sites for the use of tracking cookies, beacons, web bugs, or offsite javascript includes? As far as I can tell, major web application scanners do not report on these attributes. One can manually navigate to sites using Ghostery and Disconnect, but doing so for a large number of URLs would be time consuming. Hypothetically one can obtain the Ghostery and Disconnect block lists, then spider a site and look for references. Still, it would be nice if there was a clean cut tool or technique.
I'm trying to learn some attack methods by myself and I have hit a wall where I can't find any information. I have successfully performed an ARP MiTM between 2 systems and I am able to sniff the traffic using tcpdump, driftnet, etc. My question is: How can I actively modify the packets by injecting HTML code into the response (non SSL, of course)
Is the Double Submit Cookies mechanism vulnerable anything other than XSS and sub-domain attacks? All CSRF protection mechanisms are vulnerable to XSS, so that's nothing new. I'm just wondering if I can safely rely on this mechanism so long as I ensure I control all sub-domains. NOTE: This question is a spin-off of How to protect against login CSRF?
I have run a heartbleed detector from Lookout on my Android phone. It says: The version of openSSL is affected by the heartbleed bug but the vulnerable behaviour is not enabled. What does it mean by not enabled? I can see /system/lib/libssl.so file on the phone and found openssl on it. It shows 1.0.1c. Does that mean my phone is vulnerable to heartbleed bug? My other question is: How I can check whether a particular Android app is vulnerable to heartbleed or not? I don't want to use any third party app. I have seen https://github.com/musalbas/heartbleed-masstest/blob/master/ssltest.py but I want to do it with an app. I don't know the domain name the app is communicating to. Are the app bundle the OpenSSL libraries with apk, If yes how to find the version of OpenSSL being used. @Solution: I have wriiten python module which takes an APK and it do the check for openSSL version and heartbeat extension. import zipfile import os import re def heart_bleed(tempdir, msl_outputfile): parrent_tempdir = tempdir.split('tmp')[0] sslpattern = re.compile("1.0.1[a-f]") flagssl = False flagheartbleed = False msllst_heartbleed = [] msc_vulid = "heartbleed" msc_infoseverity = "Info" msc_medseverity = "Medium" apkpath = '' if (parrent_tempdir): for root, dummy_dirs, files in os.walk(parrent_tempdir): for allfile in files: if allfile.endswith(".apk"): apkpath = os.path.join(root, allfile) #print(apkpath) with zipfile.ZipFile(apkpath, "r") as msl_apkread: for i in msl_apkread.namelist(): if i.endswith(".so"): data = msl_apkread.read(i) if "part of OpenSSL" in data: start = data.index("part of OpenSSL") resultdata = str(data[start:start+40]) sslversion = re.findall(sslpattern, resultdata) if sslversion: flagssl = True if "tls1_heartbeat" in data: flagheartbleed = True if flagssl and flagheartbleed: print("The App is using OpenSSL version " + sslversion[0] + " which is vulnerable to Heartbleed and Heartbeat extension is enabled.")) elif flagssl or flagheartbleed: print("The App is using OpenSSL version " + sslversion[0] + " which is vulnerable to Heartbleed but Heartbeat extension is disabled.")) Please comment is it right to do ?
I have a server located in the USA and SSH to it from various places around the world. When I SSH in from a computer I have never used before, I'll see something like this: The authenticity of host 'my.usa.server.com (11.22.33.44)' can't be established. RSA key fingerprint is xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:b8:1d:61. Are you sure you want to continue connecting (yes/no)? From most places in the world, the RSA fingerprint is identical, which makes sense, because I'm always connecting to the same server: [From a server in Sweden] me@sweden:~$ ssh myaccount@my.usa.server.com The authenticity of host 'my.usa.server.com (11.22.33.44)' can't be established. RSA key fingerprint is xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:b8:1d:61. Are you sure you want to continue connecting (yes/no)? me@sweden:~$ [From a server in The Netherlands] me@nl:~$ ssh myaccount@my.usa.server.com The authenticity of host 'my.usa.server.com (11.22.33.44)' can't be established. RSA key fingerprint is xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:b8:1d:61. Are you sure you want to continue connecting (yes/no)? me@nl:~$ [From a server in the US] me@otherusaserver:~$ ssh myaccount@my.usa.server.com The authenticity of host 'my.usa.server.com (11.22.33.44)' can't be established. RSA key fingerprint is xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:b8:1d:61. Are you sure you want to continue connecting (yes/no)? me@otherusaserver:~$ HOWEVER, when I try to connect from a server in China, the key fingerprint is different: me@chinaserver:~$ ssh myaccount@my.usa.server.com The authenticity of host 'my.usa.server.com (11.22.33.44)' can't be established. ECDSA key fingerprint is xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:d8:0f:01. Are you sure you want to continue connecting (yes/no)? me@chinaserver:~$ Notice that the key and cipher are different. It should be noted that I OWN the physical China server and the room where it is located, so I can be sure that the server hardware is secure. Does that mean someone upstream, such as the China government or the ISP (China Telecom) is doing some sort of MITM attack?
Is it safe to copy a private key from one computer to another over SCP? Does this depend on whether you use the same key to authenticate the transfer?
I won't really go into details of how cookie tossing and cookie overflow attacks work, because this answer explains it perfectly. This post on github explains some mitigation strategies, but does not talk about the case where a.domain.com can do malicious things to b.domain.com. The proposed solution is to host untrusted content on a second domain. For example, if we run mycompany.com, we should store user content on a second domain like mycompany-users.com. Let's say we have this scenario: Our company provides a SaaS service for our customers. Each customer will be given their own URL to login and use the service. Customers are allowed to customize the look and feel of their instance by modifying the HTML, css and javascript of their pages. In this case, we have company1.mycompany-users.com and company2.mycompany-users.com. Let's say a malicious employee called Mallory at company1 implements some javascript that uses a cookie tossing attack or a cookie jar overflow attack to set or replace the cookies on .mycompany-users.com. An employee at company2 is then tricked to visit that page on company1.mycompany-users.com and have their cookies on .mycompany-users.com replaced or modified. Since the server does not receive the domain of the cookie, we cannot filter out cookies by their domains. Provided that the app is secure, the attacker cannot read or write to information on company1.mycompany-users.com. In addition, session ids are regenerated on login. However, it still annoys people because the session data is damaged and if the user is logged into company2.mycompany-users.com he would be logged out because the session id is invalid. Besides forcing customers to buy their own domains, is there anyway to prevent malicious people at company1.mycompany-users.com to cause users at company2.mycompany-users.com to logout due to cookie attacks?
Given that user needs to store a copy of the same private key on each of his devices (in order to decrypt email and other data encrypted with the public key) ... what are some general techniques for sharing and optionally removing the private keys from a user's various devices? Would a file sharing service suffice? Do most SMIME or PGP deployments assume that the key is only stored on the smartcard or other device?
I was wondering, a lot of software nowadays automatically connect to a server at launch to check for updates, even basic software, and, to my knowledge, this is a new trend. Before you had to download it all again from the website. My guess is that some of them weren't designed with security in mind and simply check an FTP or non-SSL HTTP, thus allowing a pen-tester that succeeded his MitM to easily take control over the computers, assuming the user launched the software and accepted the update. My question, thus, is: Is there someone out there that publicly keeps a list of those vulnerable softwares? With a little work, it could be implemented into Metasploit in the same fashion as the Browser Autopwn was for an easy, fool-proof exploitation : redirect the query for an update check version of software create corrupted but working executable with higher software version Delivery I know that the probability of success isn't great if you only have 1 rogue update server for a tiny program nobody uses, but if you have 1 rogue update server for all of them, that could be interesting. Second question: is there a public tool that does the 4 points described above? (i know you would have to know how to communicate with each program, and that might be time consuming, but still).
A website based on Apache Struts uses central authentication service (cas) for login. I'd like to know if additional csrf protection needs to be provided with Struts in case cas doesn't provide that. Also, when credentials are submitted, cas generates a token in URL form. If I copy this URL and use it later, the user is authenticated and redirected to the home page. As I'm not logging in, but just using the token URL, why is this happening? Is this a security vulnerability?
It is generally accepted that password change mechanisms should ask the user for their old password (e.g. OWASP) The reason being that an attacker who has temporary access to a user's session (be it through XSS, computer left logged-in, whatever) would only have access to that session. Presumably this principle should carry forward to other authentication mechanisms - certificates, tokens, etc. (although I've never seen this discussed) However, consider how SSH authorized_keys works. If you have access to a user's login session, but not their keys (e.g. they left their computer logged-in) then you can modify the authorized_keys file. You could add your own key to the file, so you could get access to the account in future. You could also remove the legitimate keys to lock out the account owner. So should the SSH designers be looking at ways of tightening this? And what approaches could we take to stop this vulnerability?
I want to improve the security of my home wifi. My neighbor wants to crack my Wi-Fi password with a nutcracker. I tried to activate the protection by MAC address, but now my laptop and smartphone don't have access to the box. Is MAC address filtering effective? How else can I secure my Wi-Fi?

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