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While browsing PasteBin today, I noticed a new Paste that outlined approaches to compromising TrueCrypt protected data, as well as full Keys, Encryption Schemes, Plain-text Files, and Volume Names (and metadata). It was terribly un-nerving. Appears this Pastebin was copied from this blog post, "TrueCrypt Master Key Ex...
I'm researching XSS vulnerabilities in a web application which uses continuations. That means that for a given form, the URI the form data is posted to is unique and different every time. A first GET request displays the form with its unique URI such as: http://test.local/webapp/4b69615449222508116a1e562e1e0a458e4d635...
Similar to how it can be easily done for RSA: openssl req -x509 -nodes -newkey rsa:2048 -rand /dev/urandom -keyout example.key -out example.crt -days 365 I'd like to generate an ECDSA cert/key in one step. I've tried: openssl req -x509 -nodes -newkey ec:secp384r1 -keyout ecdsa.pem -out mycert.crt -days 30 Returns the...
I received an email from my web host recently that informed me I had an "insecure" password on one of my email accounts and that I had to change it. Their definition of what a secure password is as password that contains: Mixed case - Always use a combination of uppercase and lowercase characters Numbers - Always use a...
Lets say I can control the EIP CPU Register, and I want to jump to a specific function of which I know the correct memory address. This address is inside the same memory page. We have no exploit mitigations enabled. Can I then just pass the memory address of the function to jmp and load that into EIP?
I was wondering what some of the potential abuses could be for an HTTP API that accepted SQL queries and output results sets. The fact that this is the canonical definition of SQL injection is not lost on me :) In my case, I have a specific PHP/MySQL application in mind which is Magento - an eCommerce platform. Here...
In terms of PCI requirements and compliance, is a software-based key management module like Gazzang zTrustee an acceptable solution to the PCI requirements that a (hardware) HSM solution like AWS CloudHSM solves?
A problem with many challenge-response login systems is that the server has to store a password equivalent. For example, if the server stores SHA1(salt + password), and an attacker captures that hash, then they would be able to directly use the hash to login, without having to crack the password. I believe there are so...
Is there a way to include my own attributes into an openssl certificate? e.g ... Country Name (2 letter code) [GB]: State or Province Name (full name) [State]: Locality Name (eg, city) [City]: Organization Name (eg, company) [My Company Ltd]: Organizational Unit Name (eg, section) [Section]: Common Name (eg, your nam...
We're building a public single page app in JavaScript that talks to a back-end REST service. What we want is for that REST-service to be only accessible from the single page app. Since it's a public website, we can't / don't want the user to enter authentication details. Any normal authentication mechanism won't work ...
I'm wondering whether an HTTPS API endpoint would be as secure as or more secure than SSH. API Endpoint The API endpoint would require HTTPS The API authentication would use a POST'd API key. The minimum required length of the API key could basically be arbitrarily long The API endpoint would only accept connections...
Some services like Github has DDOS mitigation measures for their root/naked domain, but not other subdomain(s). What so special about the root domain concerning the DDOS attacks? [1] http://instantclick.io/github-pages-and-apex-domains
Last week I was told by our security department that my PC (running windows 7) was infected by a trojan and that it needed to be re-imaged. So re-imaged it was! Given the fact that I had been using this PC for a while, visited thousands of web pages and used USB key to 3 days later, the security department notified me...
I am thinking about an anonimity network (just as tor), but using some type of guarantee against mis-usage. For example, which torrent does: there is a tracker, which registers who has given how much how many pieces of a file, and uses this data to help or stop the actual downloader. I am thinking about the same thing,...
I am thinking on a system, which measures the complexity of a password not based on its entropy or compressibility, but with a simply sophisticated method. The measurement of the entropy/compressibility are measuring the idea, "how hard is to build this password from bytes". I am thinking on a method, which measures "h...
If I connect to an evil twin wi-fi hotspot, aka rogue AP, among other names, are only the data being transmitted at risk, or, are the data on my HD also vulnerable? I am working with Windows 8, updated.
Please excuse my probably gross misunderstanding of how all this works. I just started reading SSL & TLS Essentials by Stephen Thomas, and in chapter 1 he talks about how TLS is a separate protocol layer below the HTTP application protocol, and since it is a separate layer, different application protocols may use it (s...
I'm playing around with Snort's downloadable rules and I found one which is easy to activate: sending a unicast ARP request. Okay, so I start injecting ARP requests, making sure the destination is not set to broadcast. And sure enough, Snort picks it up. Great, let's move on and do more complex stuff. Though, I'm not s...
Considering that I have a structure like the following, allowing only the TCP and UDP ports for SQL to be accessed. Specifically no traffic initiated from SQL is allowed to reach SECURE. SECURE-> SQL <- STANDARD |-> SECURE-SQL What kind of attacks are there out there to compromise SECURE - and therefore eventua...
I've looked on this site and on SE. but I couldn't get a handle on this. Is there a way to find what type of encoding (and/or encode key) is being used? For example, I am testing a web application(PHP) which will encode the links before it will be showed to the end-user. For example, the source link is: https://www.am...
Traditional situation It is easy to crack a ciphertext encrypted by Vigenere cipher, if you know the plaintext is in a natural language like English. There are two methods to discover the key used to encrypt the plaintext. Either you know frequencies of certain characters that will occur more often than others (e for E...
I am trying to do a Snort demo and I though it would be nice to detect a real threat. I picked the sasser worm and the jolt/teardrop dos attacks for the demo; no particular reason. Out of the three only one, the teardrop attack, is detected. I have tested snort with "testing rules" (alert every tcp packet, search for a...
According to the documentation a hidden volume stays hidden because it appears as free space. In TrueCrypt free space always has random data in it, however in the case of a hidden volume it's not actually random data but the hidden volume. I was wondering how is it possible to write (for example add a new file) to the ...
I'm setting up a Tor-based isolating proxy using the 'Anonymizing Middlebox' iptables rules specified here: https://trac.torproject.org/projects/tor/wiki/doc/TransparentProxy i.e. iptables -t nat -A PREROUTING -i $INT_IF -p udp --dport 53 -j REDIRECT --to-ports 53 iptables -t nat -A PREROUTING -i $INT_IF -p tcp --syn ...
While reading up on iptables, I saw this article from NixCraft recommending that a server block the following bad addresses: 0.0.0.0/8 10.0.0.0/8 127.0.0.0/8 172.16.0.0/12 192.168.0.0/16 224.0.0.0/3 It doesn't say whether it is applicable for UDP, TCP or all traffic. My web server has an application running on TCP 12...
In a study project i have to plan a network for a small company (around 50 employees) and i am currently at the point, where i want to design the database architecture. I read that its common to have a web server in the DMZ. The company has got an online shop. So it is necessary to access a database. Customers can crea...
UPDATE: The source of this problem has thankfully turned out to be a buggy mobile SSH client used on 2 different devices not a MITM attack. However, I'd still appreciate a full answer to the original question: Namely, in the event of a genuine MITM attack, what steps should an administrator take after detecting it? Doe...
I have a free ssl certificate issued just before Heartbleed was found. Now my CA wants me to pay 25$ to revoke it. Should I pay or it's just enough to create a new certificate from another CA an replace existing? Considering there are no real users of my site (the site is still in development and nobody has my old cert...
Visiting this site: http://ruby-doc.org/ I get this message: There were 3 Ruby vulnerability reports in the last 14 days. 2 high, 1 medium. Most recent: CVE-2013-4562. See details. I only installed ruby for fun and to play with it. Does this vulnerability affect me? I'm really afraid what should I do?
Do you know if AVs scans non-persistent memory mapped file content in a Windows Environment ? (Or have the answers for some of the AV on the market) I would prefer, if possible, some real world testing or white paper, more than commercial speech from the AV developer. ALso, do you know where I can find recent documenta...
I have a server which has 'loose' physical security (somewhat easy for the entire server to get stolen). For the sake of the question, let's assume that anyone can access the server physically, what precautions should I be using to keep the data secure? My initial thought would be to keep all logs, databases, user cont...
Could a hash function like sha1 or ripemd-160 be used for secure key generation in a stream/block cipher? Obviously a repeated key like "abc123abc123abc123" would be bad, and a one time key pad would be impractical for large data... but what if one used a hash function to derive new keys from the origional password lik...
Given that I have an initial input that is publicly known (e.g. "ABCDEFGHIJ") a slight variation of (1) (e.g. "BACDEFGHIJ") that is used as the input to a hashing algorithm (3) an modern one-way hashing algorithm like BCrypt, Scrypt etc. the result hash of (2) applied to (3). The hash is also publicly known. How easy...
Reviewing openssl 1.0.1g s23_clnt.c code i see that : int ssl23_connect(SSL *s) { BUF_MEM *buf=NULL; unsigned long Time=(unsigned long)time(NULL); void (*cb)(const SSL *ssl,int type,int val)=NULL; int ret= -1; int new_state,state; RAND_add(&Time,sizeof(Time),0); This RAND_add(&Time,sizeof(...
All questions ask about the other way round, ie. can a virtual machine compromise the host. But I'm asking can a virus on the host machine compromise the guest virtual machine?
Would anyone be so kind so as to describe to me the Serpent-256 cipher? How does it work and how secure is it compared to AES? I have searched everywhere and found scarse info about it. Anything related to it (speed, security, mode of operation, programs which use it, etc.) are highly appreciated.
As I am working on a research, I need allow users to read my JavaScript file using Ajax. However, I want to make sure about consequences of adding Access-Control-Allow-Origin header for just this file. Access-Control-Allow-Origin: * I know about the goal of origin control and all examples about accessing behalf of use...
I administer an Ubuntu Server 14.04 which acts as a mail server running Postfix and was configured following most parts of this tutorial: http://www.pixelinx.com/2013/09/creating-a-mail-server-on-ubuntu-postfix-courier-ssltls-spamassassin-clamav-amavis/ I have ports 25 and 143 open to the public use STARTSSL communicat...
I want to understand how a vulnerable internet facing process on some computer is exploited to run arbitrary binary code. I understand how buffer overflows could be used to overwrite the return address to make the process jump to a location it wasn't supposed to - but I don't know how it's possible for a process to exe...
I have identified a stored XSS and I'm wondering, how could I leverage that vulnerability to upload a shell.
There's a file processing service that looks for some know attacks and sometimes returns messages like: Probably harmless! There are strong indicators suggesting that this file is safe to use. Are there heuristics that model the likelihood that a file is harmless, and if so, what is a simple example of such a heuri...
I am writing a service-oriented (REST) application that is (nearly) totally stateless: it can authenticate by API keys, but for web UI it uses the session where it stores nothing but an authenticated user's ID (int). Session ID is generated randomly as it's usual to see, user ID's are never exposed to the users as user...
My friend just posted a picture of her key to instagram and it occurred to me that with such a high res photo, the dimensions of the key could easily be worked out. Therefore the key could be duplicated. What's to stop someone malicious from abusing this?
I would like to move from sequential to random user IDs, so I can host profile photos publicly, i.e. example.com/profilepics/asdf-1234-zxcv-7890.jpg. How long must user IDs be to keep anyone from finding any user photos for which they have not been given the link? Does 16 lowercase letters and zero through nine provide...
I may have to visit family in a few months overseas. Unfortunately, the local government of the area my family is from has gotten more corrupt and vicious. I am compelled to go here and may need to use Internet while I am with my family, and I heard of creating live USB. https://fedoraproject.org/wiki/How_to_create_and...
I have two ubuntu laptops that were recently compromised. I understand that it's probably a fruitless endeavor to try to find the hacker. I want to know how to secure my ubuntu desktop so that the hacker is kept out in the future. I'd also like to know how to secure my computer against a man in the middle attack on ubu...
Recently I Googled the email address of one of my friends, as I was just curious of what would come up. Lo and behold, he saw what presumably is his Gmail hash. It is part of a list of 10,170 email addresses and hashes. First of all, I was kind of surprised that Google, of all things, would be compromised (or is it?). ...
I am developing a program that I want people to be able to connect to and use via ssh. I've decided a simple way of doing this would be to create an account for them on my linux server, and change which shell they use to login, to be my program instead of bash. One measure I can take is to remove their PATH variable so...
I have this silly question that is bothering me. When not using secure connection (HTTP for example) cookies can be intercepted and used to connect to the site as if we have the id and password. We can protect against this by using secure connection (https). This assures that the cookies sent to the server are encrypte...
I'm not sure if this is the right place to ask this question. Please tell me, and I'll delete it. I want to modify a Word document hosted on my OneDrive account. I see that it is using a SSL connection with a valid certificate (https://). I'm asking, if there is a proxy on my network (I think, there isn't), and I read ...
A German hacker famously managed to brute force crack a 160 bit SHA1 hash with passwords between 1 to 6 digits in 49 minutes. Now keeping everything constant (hardware, cracking technique - here brute-force, password length etc.) let's say it takes 1 hour to crack a SHA2-256 bit algorithm (the time taken is just an exa...
I have many applications installed on my server that use a webui frontend to control the application. Since I am the only user of the server, I usually bind these applications to 127.0.0.1. As the services are bound to localhost, I have assumed that I can disable authentication (usually username+password), for these a...
If I'm right the SSL encryption take place in the application layer, but we can also have encryption in the Internet Layer. Why are we using both, and why sites that doesn't have SSL are considered insecure even tho the information is encrypted in the Internet Layer anyway. Also is it possible for anyone in the Interne...
I've got a Kali Linux box I use for pen testing. I would like to configure my machine to DROP incoming packets, but only when I'm not listening on them. e.g. if I run a netcat listener on port 80, I would like connections from the internet to be possible, but as soon as I stop netcat I would like the packets to be drop...
I have a webserver in my windows machine running Apache(XAMPP). I have created an Android application that connect to my webserver at localhost. How can I capture the data with wireshark on localhost?
A while back I enabled SMTP on my IIS server with the intention of using it for internal email notifications. It seems that somehow hackers were able to use it for sending out thousands of spam messages. We've corrected the issue by adding some authentication to the server, but we're no longer trusted by many email cli...
I was thinking whether or not you can find the hash function(s) used if you have the original message and the hash. So assume that no salt is used during the hashing process, just multiple hashing and concatenation, e.g. hash = SHA512(MD5(original) || SHA512(original)) So how could you find the right hashing process, ...
The situation is: a hall full of 200-300 people, one of them is performing an arp-cache poisioning attack. Or messing with my network over wifi in any way. Is there a way how to determine the location of him? Using some kind of directional antenna or something? I dont need to be very accurate, when I have the directio...
Control Panel says it's 192.168.1.1; Google, whatismyipaddress.com etc. says it's 75.92.141.32 When I put the IP address reported online in my address bar I get a Nokia login page, but my ISP is Clear. I think someone may be trying to hack my computer or something.
I set up a CA and signed some cert request. I revoke them by: openssl ca -config config.cnf -revoke cert.pem I update CRL by: openssl ca -config config.cnf -gencrl -out crl/crl.pem index.txt shows a 'R' for this cert, also when I check the crl.pem the cert is listed as revoked. So I think that worked fine. Now the ...
The latest developments made it very clear, how easily basically all communication channels can be wiretapped. However, I think most people still ignore this fact. Especially in business most confidential information is still sent totally unencrypted (at least at my company). I wonder if people are unaware of the risks...
I read in an article that if the request is authenticated or secure (i.e., HTTPS), it won’t be cached. But in https, burp has reported an issue stating http response is as follows: Cache-Control: private Content-Type: text/html; charset=utf-8 Server: Microsoft-IIS/7.5 SN: SJVPROD1 Date: Thu, 15 May 2014 20:29:30 GMT Co...
I know the common usage of nonces in security (which is well described in this topic). However, when checking the SSL/TLS protocol, we can notice, according to the RFC, that nonces as ClientHello.random and ServerHello.random are sent in plaintext and could be easily replayed by an attacker. Why are they still used in...
I am looking for a way to grant access to a secured WiFi network, based on certain external information? For example, some server on the internet could store MAC addresses that ought to be granted access, in addition to MAC addresses stored in router itself. Or, access to WiFi network is password protected, but it will...
Is there a way to find out in which and/or how many computers a USB flash disk entered. And if its possible can we find out how many times a file was read/edited. I heard that its possible , but I cant find a program to do it.
PCI DSS 2.0 Requirement 5.1 states: 5.1 Deploy anti-virus software on all systems commonly affected by malicious software (particularly personal computers and servers). This requirement (although I'm not 100% positive it is the only one) caused IT security team in our company to request all the workstations able to c...
I'm using openssl enc -aes-256-cbc -a -salt for automated differential backups to Amazon Glacier. But I noticed that using this command increases the file size almost perfectly by 35%. In my understanding, a block cipher shouldn't change file size this much, with my current knowledge I know it adds at most 16 bytes to ...
I've been trying out a few desktop email clients (Windows) to better manage my e-mail. As I tried Thunderbird, Inky, and Outlook, it occurred to me, what guarantee is there that my e-mail/pass won't be compromised by using email clients? Wouldn't it be really simple for the author(s) of e-mail clients to incorporate a ...
I've been warned that PHP's $_SERVER['HTTP_REFERER'] is a common attack vector for websites. What are ways that attackers exploit this function? How can I guard against them?
I store my passwords in an encrypted database file in the cloud. That is, my KDBX files from KeePass are stored in a cloud storage server, let's say it's Dropbox. Dropbox, whether they admit it or not, probably keeps a very long history of my files. If someone were to attempt to decrypt my KDBX file, would it help them...
Is it unwise to use gmail to discuss business ideas that Google could snoop on and use to their business advantage? I know that email is not secure and anyone could read it along its path of delivery, but I feel the level of potential snooping is much higher with gmail and google than regular email. So under the gmai...
I am presently working as a summer intern. My first objective is, given a collection of files, recover and identify the file types present in it. To download sample pseudo-forensics data I have been using: Digital Corpora To recover files I have been using 'The Sleuthkit' but this does not seem to do the work as I alwa...
I am an undergraduate Computer Science student and was hoping to gain some knowledge of ways to help prevent Denial Of Service attacks.I read about some of here: https://en.wikipedia.org/wiki/SYN_cookies https://en.wikipedia.org/wiki/Port_knocking But was having difficulty as to how to start to convert them to practica...
Is it possible to exploit a vulnerable application that is running inside a process virtual machine? Let's say that we have buffer overflow vulnerability in a Java application but the JVM isn't vulnerable. Is there a way to exploit it?
At IEEE Security & Privacy, the blind return-oriented programming attack (blind ROP) was just introduced. In some sense, this is just another variation on ROP attacks -- but the blind ROP attack is notable because it does not require any knowledge of the source code or the binary of the program you are attacking; you ...
I have the need for a company laptop (Dell e6540) that contains our java application on it to go out for evaluation purposes. For this reason I would like to make sure that the HDD is protected from customers (or anyone else) being able to take our java app off of the laptop and view the source. We have taken many ne...
I'm working on the authentication strategy for my app (again). My current strategy is a clone of the AWS strategy of issuing public and private keys and using them to sign requests sent to my API. My understanding is that this is a reasonably secure way to authenticate API consumers. However, AWS is phasing out this pr...
I have to go through background check. The company providing the service to the client is called Verifications, Inc. Verifications, Inc claims to have a data security plan, ISO certification and US Federal clients. I was surprised to learn the company provides a web based system and sends the username and password via ...
Would just like some input on a PHP script I'm writing. It's just a simple script that only myself should be able to access. I don't have a dynamic IP address, so this isn't an issue for me, but I'm wondering if there's any potential problems in my "security" measure. Currently my script is setup like this: $uip = $_SE...
What are the vulnerabilities mitigated by a tiered LAMP stack? As I understand it, any breach would allow access to the database even if it was tiered. What's the benefit? Are we better to concentrate on WAFs?
If I create a private key via: openssl req -x509 -newkey rsa:2048 -out cert.crt then OpenSSL writes the private key to the file privkey.pem and if you do not provide the -nodes parameter it will encrypt the private key. Which default encryption is used? A private key generated with this command: cat privkey.pem : -----...
Is it possible to compare encrypted private keys if you do not have the passphrase? E.g.: openssl genrsa -out unencryptedprivkey.pem 2048 openssl rsa -in unencryptedprivkey.pem -aes128 -out aes128encprivkey.pem openssl rsa -in unencryptedprivkey.pem -aes128 -out aes128encprivkey2.pem cat aes128encprivkey2.pem !-----BE...
Is there any open source alternative to Wepawet ? I need to study techniques of JavaScript malware detection.
Some web applications enable registered users to grant temporal application access to un-registered users sending token/private/unlisted/signed URLs (I ignore the exact terminology for this), which are then used to submit sensitive/confidential user information. The reason for using such mechanism is to exempt these us...
When a site gets hacked, or otherwise, the web site forces you to change your password. This is done by simply telling you to change your password, not enforcing it. Why do they do that? For instance, they could: Disable your credentials, and send you an e-mail for password reset. In case you missed the email - or you...
I've been reading up on password storage and such, and have come to the conclusion that I need to be using bCrypt. I've got an implementation working correctly, but I'm wondering the best way to move forward with my application. The previous password storage system was simply hashing and salting. It's actually easier f...
It seems to me that computer software is becoming more secure every year - there are fewer zero-day exploits to be found, many hacker-proof concepts are becoming widespread (such as virtualization and strong encryption), system administrators and users are starting to become aware of the importance of security, etc. Is...
If you run the following command on a Linux/Unix machine, among other things, you get a prompt for a password: $ ssh-keygen -t dsa Enter passphrase (empty for no passphrase): What does adding a password to your SSH key actually do? Is it more secure to use a password when prompted?
I dont understand what the problem with BigDump v0.35b. This site says that it have problem. But i dont understand it. Problem here? if (!$error && isset($_REQUEST["uploadbutton"])) { if (is_uploaded_file($_FILES["dumpfile"]["tmp_name"]) && ($_FILES["dumpfile"]["error"])==0) { $uploaded_filename=str_replace(" ",...
I just got off the phone with Fidelity, who manage the health benefits for the company where I work. Before talking to a person, I was prompted to enter my username and password on the numeric keypad: 2 for abc, 3 for def, ... (Their passwords are limited to letters and numbers) It occurred to me that doing this severe...
Because of the eBay hacking, I had to go and look for other accounts that I have used the same password to change the passwords on those site as well. (I know that it's very bad to have same passwords across multiple sites to begin with....but it was already done) I unfortunately don't know if I was able to find all th...
Why does Firefox not display the SSL logo when viewing secure sites, i.e. sites with HTTPS? It used to display at the bottom of the browser window previously but I just noticed that that bottom toolbar is not longer displayed. When I try to find the option to turn it on in Firefox, there is no such option.
Ok I am currently storing the passwords in most secure way I could think of. With use of Encryption and Hash. The passwords are first generated by user as plain-text with minimum length of 6 alpha-numeric characters up-to 24 char alpha-numeric. After the passwords plain-text value are ran against MCRYPT. Primarily the ...
I'm someone who's distant, industry-wise, from technology. I'm actually in the medical field. That said, I'm very interested in technology and specifically in information security. I'd like to make a roadmap to be a professional Pentester and may eventually switch careers (I'm 20, so that wouldn't be life changing per ...
Is there anywhere I can download a list of checksums for microsoft-published OS executable files, preferably grouped by release name? I could do the same by decompressing files on a windows setup CD, and checksumming them, and then doing the same thing to all installed updates via WSUS and some scripting, but this seem...
I know that it's possible to decrypt a sniffed SSL session even when some packets were lost during the capture. I run some tests with wireshark and I saw that it's still able to decrypt part of the session. I'd like to understand better how this works. My guess is that each SSL record is encrypted separately, therefore...
When you are connected to another computer over SSH, is all data transferred between the two computers encrypted? Or is any data sent in plaintext or any other "easy to intercept" format?
Our small comapny wants to launch a paid service, hosted on the outsourced VPS server. The obvious risk is that the machine is physically not in our office and that possibly the database could be accessed by the stuff of the host. Are there any obvious security problems with VPS that I should consider? Second question ...
I want to add security to the system login. So here's my idea: If a user tries to login with a valid username but invalid password, then count it as a failed login attempt and store it in the users database for that specific user. After X failed login attempts for that user, take some specific action (eg. display captc...
The system for the internet and the way people can abuse it is getting worse and worse. I am having several issues with people abusing the information within my WHOIS, which if I remember is protected by international laws, or at least should be. Thanks to an email and what I was taught when it comes to doing business ...