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We have older firewalls that don't allow for scheduling up/down times of VPN connections, and we're working with a client that will need to connect to it at different times each day. What are the security risks (if any) of leaving open a VPN connection to a client? We have the profile completely locked down to accessin...
I've developed a client application which talks over a REST API to a server. The way the application works is to send the username/pwd pair in the initial login to the server and then respond with an auth token in the form of a newly generated GUID. The client uses the GUID to talk to the server for the remainder of th...
Suppose I want to port scan my network. Normally I'll use a tool like nmap or nessus. What if we don't have any tool to perform a Port Scan - how can we find open ports?
I currently use QuickVPN, however, it does not seem to route my web browsing traffic through a tunnel. Am I correct? It only opens up a tunnel for accessing windows shares and documents back at the office, right so only they are secure? If I wanted to also mask or make my internet browsing secure and private I would ne...
The new Firefox private browsing mode allows for both non/private browsing windows at the same time. So if a website pops up a new window (which will be in non private mode) can it read stored data? I know we can block pop-ups, but some websites seem to be able to bypass that. Wasn't it better the old way where privat...
I have been working with programs like Kali Linux, Cain, etc., and I have noticed that for the most part the biggest password stealing attacks must be performed on the same network as the victim (for instance, MiTM and most of the attacks on Metasploit). What forms of attack (especially designed to steal passwords) cou...
I would like to get a few opinions on whether it would be safe or not to use PBKDF2 to generate a hash of a password. For my purposes I'd like to assume that the hash itself will be posted on the White House Twitter page (in other words it will be public). Would I be better off using a massive number of SHA-256 iterati...
Apache Web server as a security measure relinquishes its system privileges and runs as a normal unprivileged user before accepting clients over a networks. My Question is How this measure prevents or restrains bugs to be exploited by malware. What is idea behind this approach
I'm looking for a way to find Struts2 OGNL vulnerabilities (specifically http://www.cvedetails.com/cve/CVE-2013-4316/ and http://www.cvedetails.com/cve/CVE-2013-2251/. ) I know that attackers have such tools, and there is a Metasploit module for use when you already know the exact location of the flaw. What is a good...
This paper: https://www.usenix.org/legacy/events/sec01/full_papers/song/song.pdf Explains how SSH can be compromised by analyzing the timing of the keystrokes to guess what the user is typing. It's about 12 years old. I heard that this attack vector was solved in SSH long ago by sending keystrokes at random intervals....
Django sets a CSRF protection token on the user's machine via a cookie. It then asks for the token on POST requests. If these two don't match, it returns a 403. If I change manually both the cookie and the token value I send in the request, the request is accepted. Django does not verify that the token value was set by...
I have heard several people say that you shouldn't even open e-mails that look suspicious, as you might be infected by a virus of some kind. Is there any validity to this? I suppose that some e-mails show a web page, which could be infected, but I don't think most e-mail clients would allow the page to run scripts, wou...
I'm setting up EAP-TLS on my wireless router, and am currently generating DH parameters for FreeRADIUS. First, what do these parameters do? Also, what size should they be? I've been generating the current parameters for some time: openssl dhparam -check -text -5 4096 -out dh The tutorial I was following recommended a...
I was looking at this question: How can you be caught using Private VPN when there's no logs about who you are? and everyone who read it and responded seemed to be taking for granted that every single proxy mentioned was a website. It seems to me that even programs that connect you to proxy servers don't route all of y...
My application is running an API authentication that uses tokens rather than cookies. This leads me to ask a few questions : What is the most secure way to store the token ? By using random tokens you eliminate the issue of CSRF attacks but on the other side there are no Secure and HTTPOnly flags. I thought of maybe ...
I know the real answer to the auditor. We are a smaller company under 40 total employees that is also PCI level 1 compliant. We've always used ssh keys on internal servers. You can't ssh in from the outside and have 2 factor auth on the vpn. Our auditor has always been ok with us using ssh keys since he said we are a s...
I understand that one of the requirements (and a major drawback) of OTP is that the key has to be as long as the message is. What happens if I have a key that is shorter? The message would only get encrypted partially, right? For example if my Key was "The" and my message was "Hello, there" the resulting ciphertext wou...
I am developing a Java game and money is involved. As such, I want to prevent people from modifying the client if at all possible (I'm a game designer, not a security expert). I know that it is impossible to prevent people from modifying the client, so what is a way that I could detect if people have changed the client...
I was stumped when I saw the following lines on my Apache server error log this morning: [authz_core:error] [client ::1:37317] AH01630: client denied by server configuration: /var/www/styles/style.css, referer: http://bd.adm.ijinshan.com/adm.html?adm=somehexdec&t=timestamp [authz_core:error] [client ::1:37317] A...
Note: I know how HTTP Splitting works. Note 2: I am not working in WebGoat. I am trying to make this on my own. I am trying to imitate the HTTP Splitting attack on my machine. For that I wrote this php code: <?php header("Location: " . $_GET['page']); ?> And then I enter the following URL: http://localhost/webgoat/htt...
This link describes my problem better: https://code.google.com/p/webgoat/issues/detail?id=42 I was doing the HTTP Splitting exercise in WebGoat. In this exercise, when you send a malformed URL, you are supposed to get TWO headers back. One header is the original header. The second header must be the attacker's malforme...
From what I read here, if the intermediate CA has been compromised, a fake cert can be issued and the privacy of the end-users could be compromised as well. In order to remediate this situation, someone have to report this and have this cert be revoked by the CA that issue the intermediate cert. At the end of the artic...
I was just going through the OWASP's Cheat Sheet for CSRF Prevention. Regarding the double submit cookies method, it says: the site should generate a (cryptographically strong) pseudorandom value This method completely relies on the fact that Cookie/Header can not be injected by the attacker. An attacker cannot rea...
I am based outside of the US, but I still want to watch Netflix. So I am thinking about signing up a DNS service such as unblocked-us, but I worry that as I am now querying an unknown ( relative to Google DNS, that is) DNS server, my details over the internet may not be secured, as the DNS service provider, or hackers ...
I am learning PHP+MySQL and observed that mysqli_real_escape_string function in PHP requires a identifier to a MySQL connection. From some research I found that it has something to do with charset and multibyte characters but I don't get it fully. So my question is how database connection helps in making mysqli_real_es...
To verify this, I boot my PC from Kali Linux live distro. Before establishing ADSL/PPP connection, I start Wireshark and listen on any pseudo device. Then I create the connection to ISP network. Wireshark shows PPP handshake as expected. Then, suddenly, I see incoming packets. This is a clean Kali Linux boot. I hav...
Couple days ago I gave noticed that almost all php files on my server are infected with some encrypted code and in almost every file is different. Here is the example from one of the files: http://pastebin.com/JtkNya5m Can anybody tell me what this code do or how to decode it?
My site has a search form, which queries a few tables for whatever my end users want to find. What permissions should I give my MySQL user in order to search the database and update the 'times searched for' column if needed? Feel free to ask for more information or let me know if this is a duplicate. I did spend a goo...
I have a program that generates a fixed-length 32 byte (256-bit) password using RNGCryptoService provider and then uses Rfc2898DeriveBytes on that password to arrive at an encryption key. However, to save system resources, I was thinking about just using the original password. Am I right that there is no benefit to usi...
First off, I don't know how hackers get at an entire password table and steal them. I don't know if the owners of the website are to blame or what, but I am wondering if it involves logging into the DB or not. Assuming that hackers steal passwords by logging into the DB with application or admin users, what about putti...
If we are accessing a public wifi network, does changing mac address at certain intervals of time keep us anonymous forever? Is there anything other than mac address to identify a user in an AP?
Does the Oracle Database Built-in Password Protections prevent pass-the-hash or replay attacks? Reading the "What Are the Oracle Database Built-in Password Protections?" from http://docs.oracle.com/cd/B28359_01/network.111/b28531/authentication.htm#DBSEG30031 I see AES encryption is used as well as SHA-1 hashing. I und...
My setup looks like this: In the interest of security, I'd like to separate the wired network (where the Workstation is plugged in) from the wireless subnet. I don't trust some of the devices in the wireless subnet - they are vulnerable to malware and risky because torrenting warez. I'm not interested in the network i...
So now that I have to implement "secure transport" as defined by The Direct Project (not to mention reinventing a bunch of wheels, but that's another story for SO), I find myself staring down the barrel at having to create several dozen internal users' S/MIME certificates since (for obvious reasons, I think), I'd very ...
I am trying to establish 2 way SSL connection with remote server and I have received certificate to connect. Can somebody explain behaviour described below. I am able only to use it with SOAP UI which uses Java SSL libraries. However all other software such as browsers and .Net applications fail. Chrome returns this er...
I use the Spring security for Java web applications and I have written an authentication provider which is working without salt and now I want to either add salt or alternatively use the built-in algorithms with Spring security that appear to be SHA and that can use salt that is specified with XML. In my case I didn't ...
During a penetration test‎ (exercise) on a IIS web server + MYSQL DBMS, I have found an Unrestricted File Upload vulnerability for which I can upload a .php file. So I have tried to upload a php shell using a passthru or an exec command but I have received the famous response "Unable to fork..." because, as far as I un...
I'm a software developer with an interest in and basic level of knowledge about security. I've come across an authentication system that "smells bad" to me however I lack the expertise to know what if anything is wrong. The software system involves web services for downloading and uploading data from/to a database over...
They way I understand DeAuth-ing a user on a wireless network is this: The attacker pretends to the AP he is the user and to the user he is the AP. He then tells the AP (as a user) "I need to re-authenticate!" and the user (as the AP) "You need to re-authenticate!" So why aren't networks set up by default so that only ...
For an Authenticode signed file to be verifiable by Windows after the original signing certificate has expired (typically 1-3 years after issue), the file also needs to have a cryptographically signed timestamp that Windows can verify. There are a number of Authenticode timestamping services that will sign your binary ...
With data mining tools like Maltego and other correlation tools for large data sets, if we conduct any transactions online assume that these can all be collated to build a good picture of what we do, buy, read etc (hence Google etc). If a normal person, with a large online history decides to go off-web, is there an eff...
I'm looking into increasing my use of signed and encrypted "things" - LibreOffice Documents, Off-the-record chat, PDFs, emails, etc. I'm finding that some things only support x509 format-certificates, and others only support OpenPGP format-certificates. I also like that OpenPGP is not CA-dependent, and dislike that the...
One of my friends used to boast about how long his passwords are. One day, I decided to play a prank and social-engineered it out of him. I was pretty surprised as to how effortless the entire procedure was, and how oblivious others can be. Many of my acquaintances don't seem to understand the dangers of social enginee...
What is a technical difference between "grey padlock" and "green padlock" in URL bar in browsers? As an example we can take: Green padlock: Bank of America Grey padlock: Google Search Both of them are signed by proper CAs. So my questions are: What is a technical difference? How does it impact my browsingsecurity? ...
A very interesting Debian security advisory was released yesterday. Genkin, Shamir and Tromer discovered that RSA key material could be extracted by using the sound generated by the computer during the decryption of some chosen ciphertexts. How does this attack work? What are some possible mitigations?
Scenario I have many set top boxes that feel sluggish when accessing HTTPS websites. I would like to find out which SSL cipher suites are most appropriate to use for our websites, so that the boxes perform optimally. Unfortunately the OpenSSL command line tool is not available on it so I cannot benchmark it that way. I...
i need bcrypt to create encryption keys and also for authentication hashes, but entropy of delivered output from password has to be >256bit (which clearly can't be achieved by hashing 196bits with SHA256). is there any bcrypt implementation that use SHA256 in KDF? if not please help me how to do that myself Scrypt is ...
/GS compiler option Micorsoft developed added an extra cookie before the return address and before returning the cookie is checked, if it is intact then return address is safe why ever would this assumption hold ? In my understanding this just makes hacker's lives a bit harder to now keeping the cookie intact.
It is a known fact that your laptop camera can be hacked to spy on you. While the most often mentioned remedy is very low tech yet effective, everyone seems to omit the fact that the microphone can be used to spy on you too. I have no proof but it seems probable. Is there any remedy to this except for the general "ma...
First off - I usually target my questions to StackOverflow since they're programming related, and I usually login with my work account - so this will be my first post from this account, as well as my first post to this site - so I apologize if this question belongs elsewhere. I have Eset installed on my Windows 7 machi...
We need to implement seamless SSO with ADFS SAML 2.0 using OpenSSO & we plan to go with IdP initiated GET binding. The user in client network will log in to ADFS with Windows credentials once every morning. Thereon, whenever he accesses our application hosted in SaaS environment (different network/domain than that of t...
How does an IDS identify a computer on the network. I mean do IDS' actually check whether a device is actually what it claims to be ? If so what factors does it check (MAC etc) ? For e.g. if a device was banned from the network due to malicious activity (My friend claims that when he tried ARP spoofing in his college;...
Situation: An e-commerce system (specifically: PrestaShop) which is used to sell virtual products (specifically: product license keys). To accelerate order processing, a cronjob is supposed to be regularly executed which looks for new orders. Each of this order is checked against a list of criteria, if it passes the te...
If I follow the reasoning of a colleague it seems you should never run Apache Webserver or Tomcat on a Windows server if you want to keep the https certificate safe. Let me explain before this question evolves into a Windows vs Linux troll battle. For example when using Apache Tomcat for a https website the private key...
So I'm working from a local cafe, doing some web development, and need to see something in my Apache's access log. And to my surprise, in the log I see, every 30 seconds or so, a request for my root web page, coming from 192.168.1.1 -- the cafe's Verizon router. Is this a normal or known behavior? Or is it Bad? The we...
In a software project, a software vendor is responsible to deliver a piece of software. Everything else, including the infrastructure setup, database and application server installation/configuration/maintenance, etc. are not the responsibility of the software vendor. Contractually, the software vendor is to provide BC...
I've been wondering lately if RC4 is so flawed in all its forms, why is it that it is still being supported by all major browsers per default? Why does the typical chrome browser prefer ECDHE-ECDSA-RC4128-SHA over ECDHE-ECDSA-AES128-SHA?
For someone who has a key and ciphertext, is it possible to find out what encryption algorithm was used?
I am wondering if it is safe to send "id token", which is one of the items that are result of authenticating a user using Google Open Id Connect, to the client and use it for further authentication. The other item that is significant is the access token. My idea was to send the id token to the client, and keep access ...
We use Google Authenticator and SMS for two factor authentication. Should we allow the administrators of the site to turn off TFA for users? Google Auth uses SMS as backup option but SMS does not have a backup and when the user cannot receive SMS for whatever reason he/she cannot login. I know we can backup SMS with vo...
Is it possible to steal a non secure Cookie (Secure Flag is false) when the Web Server (IIS) only allows Https?
I'm wondering if my ASP.NET Web API had an XSS vulnerability as my controller didn't have a method to handle the default GET call. Without the GET method being handled in the code a call to /api/mycontroller/?<script>alert('hi');</script> would result in: {"Message":"No HTTP resource was found that matches the reques...
I'm trying to XSS a search field and my attack vector is getting reflected like this: <input type="text" id="txtRpHiddenKeyword" style="display: none;" value="ATTACK VECTOR HERE" /> Only double-quotes are allowed and angle brackets are encoded therefore I can only use eventhandlers to execute my JavaScript. Problem is...
I have a hash thingy I am trying to decode and I have done relatively little with encryption, though I would like to try to learn some more. The hash is: 1YMTpavsFq7ykllC3CCsg3e1li31re1nROxuW1wqIqpk and I have no clue what to look for. I already tried MD5 (it failed) and I am going to try AES256, SHA-256, and AES-CBC. ...
There's a recent report in the news of a Harvard student who emailed in a bomb threat so as to postpone year-end exams. According to the report, he carefully covered his tracks using the best technology he knew about: he used a throw-away email account, and only accessed it over Tor. It turns out that this last point ...
So I am trying to find out how easy it is to crack a password using some great Linux tools. We all know about John as a password cracker and how great it is. But how about specifying a pattern. Let's assume the following policies. A password must start with a capital letter followed by 3 small letters A password must...
We have a website which stores hashed passwords in the database. During logins we hash the password entered by user and compare two hashes. This is quite standard so far. Our client which is in finance domain now wants us to implement a feature where we would ask users to enter few random characters from their password...
Is it possible to have OpenSSL trust a non-root CA such that a certificate signed by that non-root CA can be properly verified? I've noticed that the default behavior for OpenSSL is to only verify certificates when it can build a complete chain, up to a self-signed root CA. Can this be overridden? I specifically do not...
If Apache is configured to parse PHP and not allow to index files, are there other ways users can see PHP source code, either with or without intention?
I have been attempting to run a MiTM on a very old XP SP3 computer. I have attempted it with 3 products, as listed below: Wireshark: Traffic from the computer did not even show up. (I did see traffic from multiple IP's, so I think I have the right adapter) ARP Spoof: (with and without SSL Strip): As soon as attack took...
I have a BlueCoat ProxySG 810 appliance and want to use it as both an HTTP Proxy Server for clients on the Inside interface of a PIX 525 Firewall (OS Version = 8.0(4)) and a Reverse Proxy Server for my Web Servers on the DMZ. Should I place the ProxySG 810 on the DMZ? If I do so, does the ProxySG 810 need to be allowe...
Today like many other times in the past, signed for a new service and got a common error message: Your user name or password is invalid This time I am wondering how useful it is to notify "invalid password OR user" versus a less common but more useful two message schema with the real problem: "unknown user", "invali...
I am wondering how could a zero-knowledge host such as mega.co.nz prevent users to just upload files in clear, and, for example, to discredit the site by uploading a large quantity of illegal material and then telling the authorities. Ideally, the server should refuse unencrypted uploads. However, what's a definition o...
I found myself looking at a stock and forex search page when I try to access Chinese Stackexchange using my FireFox browser today. This is what the page looks like: And this is the HTML of the page: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd"> <!-- turing_cluste...
So http://en.wikipedia.org/wiki/SHA-1 SHA-1 produces a 160-bit (20-byte) hash value and As of 2012, the most efficient attack against SHA-1 is considered to be the one by Marc Stevens with an estimated cost of $2.77M to break a single hash value by renting CPU power from cloud servers With a theoretical attack tak...
Suppose I'm suspicious that one or more (pseudo)-random number generators is cryptographically flawed, perhaps even deliberately backdoored. The RNGs in this case might be either PRNG algorithms, hardware random number generators, or some OS-provided primitive whose source might be either of these. Can it ever be a ba...
Are scripts coded only using the default API of a high level, interpreted language for generic and meticulous gathering of network device and host software information that are already available through common network security applications able to go unnoticed at times that common network security applications would se...
Current full disk encryption on mobile devices rely on low entropy passwords like PIN numbers or pattern locks. Being able to use a smartcard with such mobile devices is a tempting idea. I know that some implementations of smartcards are weak against physical attacks like using acid to recover the key or other side cha...
So I have been hearing that using WPS Pin is not secure at all and that there are available downloads that can brute force attack the pin until it uncovers it depending on what encryption you use. I have done a little digging but I cant conclusively discover what is the most secure encryption to use. I was wondering if...
Assume that a visitor to a website has changed his useragent to something like the following, but he's using linux: Mozilla/5.0 (Windows NT 6.2; rv:20.0) Gecko/20121202 Firefox/20.0 Assume that the website is in the hands of an evil hacker. Is this trick enough to make the expolit-kit nonfunctioning, or is it possible ...
The Raspberry Pi has a built in hardware random number generator but there doesn't appear to be any public documentation on the hardware, and even if there were it would be questionable (what company is going to publically admit that there might be problems with their own hardware if they can get away with it?). So the...
I have noticed recently on OS X Mavericks that running sudo will not only allow one to run it again in the same window or even the same application, but will permit any application to run shell commands as root. This would mean that any application continually trying to run sudo without a password in a loop would gain ...
In the last few weeks I have been getting an increased HEAD traffic to my website of the form HEAD / HTTP/1.0" 200 0 "-" "-" This just returns the details of my web server, right? The IPs are from all over the world. Any idea on why this started suddenly? I do get the usual attacks infrequently, but this HEAD traffic ...
In this thread, Tom Ptacek explains what Password-Authenticated Key Exchanges are, and it got me really interested in them. If I'd like to start learning about how to build them into real world software communication protocols, where can I find a starting point for information on understanding and implementing TLS-SRP?...
I've recently read Ned Batchelders article on UTF-7 XSS-attacks. I tested his examples, but could not get any UTF-7 attack to work in modern browsers. I tried recent versions of Firefox, Chrome and Safari so far. I know that Chrome has some XSS-attack prevention mechanisms but to my experience, Firefox has a more "gene...
Is the ARM processor used on the Raspberry Pi vulnerable to standard buffer overflows? That is, if a program that has a BO vulnerability is run on a Pi, will it be vulnerable to exploit? How does the unique architecture of ARM and SoC affect the vulnerability, or the exploit? Considering the lower footprint and sm...
I'm using a TP-LINK TD-8817 ADSL home router with a customized firmware from my ISP. When using the modem in router mode, I often redirected to a specific link owned by ISP. This is interesting because I never have this problem in my old router. So I used tftp to retrieve router firmware (a file called ras). Then I ...
I'm new to encryption and still learning about it; I overheard someone this weekend mentioning that 4096 bit encryption was "cracked" by listening to the CPU and searched for this to confirm it because it sounded a little hard to believe. However, at least if this article is legitimate, it appears to be true. Accordin...
If you are exchanged email messages with people using Linux, Windows and some odd Mac and want to implement some really basic security, encrypting all messages, just trying to avoid some non-sophisticated attacker. Is there a tool already installed on these systems by default? Alternatively, a compatible procedure that...
The haystack theory is the recommendation to put repeated characters in your password in order to make it harder for brute force to reveal. Does this have any mathematical basis? Or is it snake oil?
I have transmission-daemon setup with RPC enabled using a whitelist. The whitelist contains only 127.0.0.1 and my virtual private network range of IP addresses. I connect most of my devices through an openvpn server, and so I am wondering why I would need to enable standard auth (user/password) for services that are on...
VPN service providers such as ProXPN offer a service in which you pay a monthly subscription, allowing you to download an app for Windows or Macs so that your traffic goes to the internet via this protected tunnel. The problem with this is that I don’t want to have to install the app on every box at home. I have an ol...
I want some advice on my Authorization/Authentication scheme that I will be using for my Web API that I am writing. Firstly the Authentication : 1) When a user first logs in and they are authorized, I send back a unique token back to the client. This token is used in subsequent API requests in order to authenticate th...
PPTP is not an open, ratified standard the way that, for example, SSL/TLS is. (see: http://en.wikipedia.org/wiki/Transport_Layer_Security#TLS_1.2 and http://datatracker.ietf.org/doc/rfc5246/ ) The most popular (most widely deployed) implementation of PPTP came from Microsoft, in WinNT. This implementation was also used...
The scenario I'm trying to address is this: There is a web application Y which has an authenticated user. Inside Y, web application X is hosted (which belongs to a different domain). When X is launched from Y, we want the authenticated email address from Y to go to X. X is launched by hitting a url belonging to domain ...
Let's say I have an encrypted message. I want to make it so that someone is able to decrypt it. The only way of giving it to them is online. For the purposes of this question, I can't call, mail or meet them in person. I want to ensure that only they are able to decrypt it. I know that the method of communication (wha...
I recently began configuring our production server for a new Drupal site. Up till now, I've always used the default PHP handler mod_php, and removed write privileges for any directory/file except where image uploads, etc may occur. The vps we purchased is from a company that actually removes this from the WHM configu...
Excuse me for question name, but I couldn't find any other suitable title. I want to validate client connecting to the server. My algorithm looks like that: Clients sends his login - plaintext Server sends random big integer AES encrypted with password corresponding to the login Client decrypt number using his passwo...
All the clients in my wireless network send continuously arp requests to a host that doesn't exist (I've checked its absence with nmap -PN [IP]). The clients use windows 7 and windows xp (here the requests are sent with less frequency).What does it mean? I think that this behavior is the reason of my network congestio...
With Windows 8, Microsoft introduces the Metro Apps which run in a sandbox environment, and therefore should be more secure. I would be interested to know if this higher security that the metro apps bring to the Windows OS also apply to the Chrome Browser, that is I want to know if there is any advantage from a securit...

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