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I've usually been told that public key authentication is strongly preferred over password authentication for SSH. However our previous admin was against public keys and only issued passwords and took care to use different passwords for different servers (pwgen generated passwords; they are reasonably difficult to brute... |
This blog is describing a way to hide the referer header in various situations. Specifically he is referring to things that run in the about:blank context.
What is the about:blank context?
How does about:blank, 307 redirect, and CORS relate to this? (or how would I determine this outside of the blog?)
Are there addit... |
The vast majority of our website contains no sensitive information, logins, forms, etc. However there are portions driven by wordpress so we are looking into getting SSL to secure these areas.
There are many articles on the internet that instruct to secure the admin areas in order to harden the wordpress site, however... |
1- When a program outputs to stdout, is that normally logged anywhere else?
2- When is it an issue to make a command verbose in printing to stdout instead of working quietly or redirecting to a file?
|
You have a zip file that you created with 7z to password-protect it with AES 128. Can a smart adversary extract the data only through brute force, or is the file vulnerable to other attacks - such as, I don't know, being able to bypass the password and extract the data?
|
When I turn my notebook on, it asks me for the password to unlock the BIOS and than it asks me for the password to unlock the hard drive.
How different is this 'password to unlock the hard drive' from the so-called full-disk encryption in terms of offered protection?
If someone could reset the BIOS (which is said to ... |
When you set up your clock in Linux systems and select a timezone:
How easily can sites access this information? Can they do it through Javascript? Can they do it if Javascript is blocked?
Where else is this information leaked?
|
Do files written and timestamped in a certain timezone simply keep the -0000 time in their modification and creation timestamps and adjust the time displayed according to the user's timezone? Or do files keep the timezone information?
So if someone in timezone A sends a file to someone else in timezone B, can the latt... |
When I use GnuPG I can get a secret key saved as a file. Opening this file in a text editor I see that the key is encoded with base64. How do I find the actual prime number from the secret key? That is, how to I go from, say a 2048 bit, key to prime number?
I would like to see an algorithm that takes the file and gives... |
I see situations where you may have to input the same password more than once. You may type it in a text editor and copy it to clipboard, to paste it two or more times.
In what scenarios this could be a bad idea?
|
When you retrieve someone's information from a keyserver to add him to your pgp keyring, that is made through unencrypted keyservers, unless the user uploaded it to https://keyserver.pgp.com/. Even then, since keyservers sync with each other, people will normally add you from http connections, like when using hkp://key... |
Maybe it depends on the keyserver. Does that pose privacy issues?
|
What is the maximum number of bytes for encrypting a plaintext message using RSA that is reasonably secure and also efficient and would AES be better for the same size in bytes? The encryption doesn't have to be public by the way, I'm just wondering if AES is just as good on a short message as it is on a large document... |
I want to deploy operating system images on quite a lot of clients. I know that the images must contain the latest security patches, as well as hotfixes (assuming they are tested and approved for the target environment). They also have to be configured to receive regular updates from a certain distribution point. Moreo... |
Often on my home network I get random SSL certificate errors when I visit certain well-known sites. Today it was a Google SSL error, where Google apparently tried to identify itself as *.icloud.com. In the past we have seen errors from Facebook, Barnes and Noble, and others. It also seems to be network-wide; my desktop... |
In our organization we wanted to review the overall IT landscape and check the most critical applications for vulnerability in phase 1, and then look at lesser critical applications in phase 2... as we embarked on exercise, we realized that certain non-critical applications might be the entry point for critical applica... |
monitoring web pages for malicious iframes (root kits) without VM is not safe. when its possible to detect virtualization just by javascript, which software provide undetectable VMs ? QEMU is safe?
|
I've read that Java provides OCSP and CRL checking for CertPaths via:
Security.setProperty("ocsp.enable", "true");
System.setProperty("com.sun.security.enableCRLDP", "true");
Do these implementations check for the OCSP and CRL of intermediate CAs as well, or do they only check the leaf certificate?
|
All iOS devices from the iPhone 3GS have a hardware encryption chip, right?
When you erase an iOS device with the "Erase All Content and Settings" menu item or via Remote Wipe the encryption keys are deleted. However, the data is still present on the device in an encrypted state.
Does this mean that forensic experts or... |
Can someone break my anti DOM-based XSS javascript function using window.location?
function parseparameters()
{
var href = window.location.href;
var id = href.indexOf('#');
if (id < 0)
{
throw new Error("Error");
}
var hash = href.substring(id + 1);... |
I found this video in which they talk about crashing a website with a Ping Of Death (PoD) attack, using cmd only. How to secure a website against this type of denial-of-service (DoS) attack?
I assume it's harder to protect against it since anyone can perform such an attack.
|
Existing relevant questions:
How do you Secure VOIP in a large organization
What are the main issues and best practice security controls when exposing SIP and H.323 to the Internet?
Do secure phone lines exist? - especially advice by a certain member of the ursine race to use insecure SIP and H.323 over VPN
However, ... |
I have always wondered why so many websites have very firm restrictions on password length (exactly 8 characters, up to 8 characters, etc). These tend to be banks or other sites where I actually care about their security.
I understand most people will pick short passwords like "password" and "123456" but are there tech... |
I have a question regarding NTLMv2 resistance to password bruteforcing.
I know that some modern graphic processors (like Radeon 6990) are able to calculate billions hashes per second and crack NTLM hashes within minutes and hours.
I would like to evaluate how NTLMv2 hashes are more resistant to password bruteforcing co... |
If you are specifying requirements that a certain classification of data be encrypted while at rest (on storage), should the requirement be considered met if the data is stored on an live (turned on) system where all storage media has full disk encryption?
The storage is encrypted and will be protected if the system is... |
I know they both prevent the RESTful APIs from abuse. Hmac signed api is commonly used than the other. But I think using user/pass pair for authorization is more security, here's the reason:
To sign an api using hmac need a shared secret between client and server. So the server MUST store the secret in a computer read... |
What knowledge is needed?
What software is to be used?
How are the reports written? PS: Websites like facebook.com
|
I am really interested in the chances of BackTrack. I can't really use it but there are many videos on the web which show that you can crack WiFi with it, etc... But against these illegal things, can you prevent attacks with it also? Or is there a better OS for this?
|
I read this blogpost on how to store passwords in a database, the secure way. Elbert tells us to do this:
Generate a random salt and include something random and the username in it. Hash this.
Hash <hashed-salt><password> a lot times.
Store <hashed-salt><hash> in the database.
Regenerate the salt every time a user log... |
Does the regex [\w/$!.*-]+$ stop the injection of payloads like :
"><script>alert(4)</script>
" onload="alert(4)"
...
|
I'm a European expat living in Asia. I usually hide my credit card at my apartment. However, I'm a bit scared about losing it when I carry it (wallet robbed or lost).
That's why I already scrubbed the CVV (security code) at the back of the card thinking that nobody could use it on Internet.
However, the thread What's ... |
I don't like this idea. But I can not come up with a technical argument against it. Can somebody explain it to me? The basic idea is:
$passwd = 'foo';
$salt = hash($passwd);
$finalHash = hash($passwd . $salt);
The $finalHash is what would be stored in the database. I do understand that two users with the same password... |
An OWASP note suggests that direct object references are considered insecure in some contexts. They defined "direct object reference" as follows:
“A direct object reference occurs when a developer exposes a reference to an internal implementation object, such as a file, directory, database record, or key, as a URL or ... |
I am using TrueCrypt's 'Full Disk Encryption' and according to TrueCrypt's FAQ I should 'Permanently Decrypt System Partition/Drive' before reinstalling Windows. This does not make any sense to me. Would reinstalling Windows not undo the encryption in the first place?
The reason I would like to know, is because 'Perman... |
I'm implementing a ptrace based tool for logging system call use. It is much more simple than strace, but I'm doing this so I can learn how these tools work. I'd like to trace all user processes since they're created. Can it be achieved with ptrace?
|
I have a web app that is storing information related to a organization that I would like to encrypt but share amongst organization members. I would only like the members of the organization to be able to view this encrypted data not server admins.
It seems like I want some form of symmetric encryption. Each member woul... |
I'm afraid I'll have tomatoes thrown at me for asking this old question, but here goes.
After reading that cooking up your own password hash out of existing hashing functions is dangerous over and over again I still don't understand the logic. Here are some examples:
md5(md5(salt) + bcrypt(password))
scrypt(bcrypt(pas... |
Can someone please explain the C&C for bots ?
im reading a paper about Android bot , and its explaining something called URL flux
as method of C&C . however i couldn't really get it , so i need to know how normal bots preform c&c so i can understand this .
for example why the bot needs a public key to authenticate... |
I have received this notification on Tor Browser (Firefox). What is it?
|
Just an idea I had, and I am sure there is a lot of material about this subject, so I am looking for a pointer as to where I can find more information.
My idea is this...
When storing a password in a database, it is common to store it as a hash. This is weak against rainbow tables, which is mitigated by adding salt, an... |
I was looking into server performance when using various SSL Certificates. Specifically 1024-bits vs 2048 vs 4096. It turns out, it makes a big difference!
I've heard a lot of talk lately about vendors issuing 2048 certs by default nowadays and was wondering what the consensus is in the community.
My line of thinking i... |
This is an purely educational question:
Suppose we have different cloud storage providers. Imagine a files as a stream of bits and we save each 'th byte on the ( module )'th cloud provider's storage space.
Q1: Would =2 be a save way to protect data?
Q2: Would some bigger than <2> effectively protect data?
Good prote... |
During the weekend I made some tests to simulate an DNS Amplification DDOS attack. sending about 90Mb/s traffic I was able to generate about x.x Gb/s amplified traffic which sent our datacenter offline in seconds.
Now that this kind of attack is getting popular every day Im curious to know best practices to mitigate i... |
I've been reading up on Authenticated Encryption with Associated Data. The linked RFC states:
Authenticated encryption is a form of encryption that, in
addition to providing confidentiality for the plaintext that is
encrypted, provides a way to check its integrity and authenticity.
My understanding is that simply enc... |
I have a server which provides a few services through the web, some of those services must be logged into to be able to use them. For these services I have implemented SSL using level 3 CACert certificates from start to end so that the transfer of authentication data and any private information is secure.
My question i... |
When i was dealing with an assistant of my bank through mobile call, she asked me to insert my bank login code after a beep.
I was wondering if this procedure is secure against a malicious agent who can listen to the data being passed.
This agent (EVE) would be listening to the call and get the sensitive data.
In Lite... |
I'm a linux noob and have an assignment I'm a bit stumped on... We're given VirtualBox (vdi) images and raw files for the state of a linux server at 3 different dates.
We're supposed to answer:
what order did people hack in and give themselves accounts?
did a certain user mess up ssh functionality for everyone?
what o... |
I realize this is a bit off-topic, but don't know where else to go to ask...
I've gotten an enormous amount of spam in the past 24 hours (hundreds), even after some relatively good spam filters. Virtually all of this stuff is hokey weight loss schemes, claimed to be forwarded from Beyonce, Pamela Anderson, et al. The... |
What security features do I need to have in-place to ensure that my website log-in and registration forms are secure?
|
On StackExchange we have the ability to choose to use our existing credentials with external OAuth providers such as Facebook or Google. This is convenient for users, but does it also have potential security advantages (or disadvantages) versus a traditional authentication model where a user would create a username an... |
When establishing a VPN connection using a hotspot, can the VPN provider identify the location from which you established the VPN connection?
|
Basically i have a computer that is dual booted with Windows 7 and Ubuntu. On the windows 7 side I do not have admin control. However on the Ubuntu side I have full control. So I want to know how can I find out the Username and Password of a wifi that the windows side has saved. On the Ubuntu side i have free range ove... |
We have a industrial system(running on linux) with a USB port. We have the USB port only for copying certain data. Other than this we don't want the USB drive to contain any other executables or scripts.etc. As end users may copy a worm/virus on to a USB device and attach to the system. What are the ways to avoid this ... |
How do you determine the model and IOS version of a Cisco router, if you have its IP address remotely, but have no physical access. For example, I run nmap -sP and can see the router's IP, but all that's shown is "Cisco", and no information is given about its model or IOS version. Assume that we do not have a telnet cl... |
Few days ago someone tried to crack my site using a Remote File Inclusion attack.
The attack was blocked by my Web Application Firewall, but I was curious about the file.
So I downloaded it started to examine it.
First of all, the file deletes itself:
unlink($_SERVER['SCRIPT_FILENAME'])
Then it starts and endless loo... |
If an application crashes, the program stops and there is nothing anyone can do about it, other than starting the program again.
Crash is a bad behaviour in general and should be avoided, but why are they seen as security vulnerability?
|
Just an open question to the security community at large because... well... the phpMyAdmin thing has made me more paranoid than usual...
Specifically, I'm thinking about Kali Linux (ex-BackTrack).
There are a lot of different (awesome) tools that go into Kali, many of which are open source. Obviously, the people actual... |
Here is the scenario:
You get to overwrite 4 (consecutive) Bytes of a Userland Remote Process in Linux without Exploit Mitigation and without the ability to inject any Shellcode and you know the Process Memory Layout. Is this Exploitable?
|
We have a customer with a very locked-down network. Any outbound connections require whitelisting of the port and IP address.
However, we are running our system behind an Amazon Elastic Load Balancer (ELB). That means that the IP address of the ELB can change and it is beyond our control.
Is it possible to whitelist a ... |
In my company, they don't allow accessing the company email or servers from outside the company network.
To access the email from outside the network, you have to use: Username, password and a number generated from a small number generator.
How does this verification method work?
|
I have a Windows SMTP server that is currently allowing the "AUTH LOGIN" method of authenticating. As I now know, this is simply a base-64 encoding of the username and password, which is basically as bad as plaintext, as spammers can sniff out the plaintext password in transit.
As a quick fix, Integrated Windows Authe... |
CAS and its alternatives all seem to require a flow like this when one service is acting as a proxy for a user when accessing a back-end service:
Service A makes a request to Service B on behalf of a user. The request includes a perishable token (proxy ticket) from the authentication server.
Service B forwards the toke... |
I'm learning about SQL injection and have the following backend code,
Set rs = server.CreateObject("ADODB.Recordset")
SQL = "SELECT * FROM Registration WHERE name='"&name&"'"
rs.Open SQL,Conn,0,1
if not rs.EOF then
message = "Your ID is """ & rs("iD") & """."
else
message = "id does not exist."
end if
I have b... |
Here's the statement: fprintf(stderr, "Some random string\n").
Is it okay not to have a format specifier, such as %s, even though the statement doesn't take any user input? Is it still potentially exploitable? It seems like it should still at least be considered a best practice to include a format specifier. I'd apprec... |
Is it safe (in terms of XSS vulnerability) to get a parameter X from the user, escape its double-quotations and insert it as href?
Pseudo-code:
Y = escape_double_quotes(X);
print '<a href="http://' + Y + '">link</a>'
|
Which vulnerabilities are common enough to become CVE? Is it related to "application"s only, or websites are accepted as well?Is a vulnerability in an unpopular website (or a local service) considered common enough?
|
Consider the following scenario: You want to securely communicate with a.com and you only trust the VeriSign root certificate.
a.com presents a certificate signed by VeriSign with CN=a.com, so you trust you are indeed communicating with a.com.
Eve has also obtained a certificate from VeriSign for her site b.com. This w... |
I'm trying to understand the security protocols on Windows from a high level as part of legal research into cybercrime, and I'm having difficulty figuring out where to focus my research.
I've already gone down the LSA authentication model path, because that is what the Flame virus used (somehow) to get itself access to... |
I recently found isaac but I'm not sure what type of encryption is possible using it. Does the random number generator itself become the message somehow or does it get used as a seed for an encryption method? If so, what; and can someone maybe give some code example in a C based language (if possible). If you just ment... |
I need to monitor and log network activities of a specific software installed on my system.
I know there are lots of network monitoring software out there, even system explorer has one built in.
I need a Windows-based application I can run in the background, it should collect the network traffic of a process software o... |
So I have an HTTP client which supports HTTPS. However, it doesn't follow the HTTP spec recommendation for redirects on POST(which is to ask the user before redirecting)
This means, in theory, if you POST to say https://example.com then it can redirect to http://example.com and the POST request will be sent in plain-te... |
One of my sites has just been hacked as this code has been inserted into random(?) files and places within the files.
Does anyone understand what it is trying to do? I would welcome anything that may assist me with finding out how it got on.
Also, any suggestions on how to stop it re-appearing? Every time I delete it, ... |
The three factors of authentication - something you have, something you know, something you are - are ubiquitous in security literature, but I have yet to find a reference to the origin of the paradigm. Can anyone shed some light on this?
|
My bank provides me with a device similar to this:
The device is essentially a PRNG, presumably based on the date/time of it's internal clock, synchronized with the bank servers.
To generate a pin the user must insert their bank card into the slot and enter their 4-digit bank card pin number using the keypad on the de... |
We are testing SPAM/Virus cloud solutions and they can read active directory users and groups to help with users set-up and configuration. All they need from me is a user name, a password and the port opening up on our firewall. By giving them a user name and password to access the active directory, what am I opening... |
I have some issues with respect to using SSL Certificates. I have a website hosted in UK and I also have an organisation in South Africa hosting my company application online for web access.
The issue now comes as I want to implement SSL for both servers as it requires login from different places and different people.
... |
Say we have a system with strong shared keys (not passphrases), and we're trying to sign messages sent by the server that will be visible to an attacker. E.g. storing session state in a signed cookie.
Is it safe to use HMAC directly with the shared key? I.e. the function will be determinant and the attacker can just bu... |
I want to know how I can achieve strong encryption of a public key present in my Android application.
It's Android's advice that
To keep your public key safe from malicious users and hackers, do not
embed your public key as an entire literal string. Instead, construct
the string at runtime from pieces or use bit ... |
I remember seeing something like this a while back, and it'd be incredibly useful for a project I'm working on. Essentially there was a list of mutex names, with a list of malware identifiers (e.g. W32/ZeusTroj) that are associated with each. Unfortunately I can't find it anywhere, and can't remember the name of the pr... |
I need to create a session cookie using JavaScript (for more info see question). I'm wondering what should the expiry date be? I'm guessing it's the browsing session, so if I don't set an expiration date this will be used as the default, right? This session would be used to validate a logged on user. So does it depend ... |
Background (not necessary to read; just what makes me ask):
Say someone's computer has either been hacked, or is running software run by $LARGE_EVIL_CORPORATION, and the hacker/$L wants to collect as much information as possible about the person whose hardware they've owned.
Now assume the hacker/$L also has software r... |
My client wants to look into hiring a third party to perform penetration tests on the website that we're developing for them. The website is just a simple 3-month contest site where people can upload their photos, and the photos are judged by moderators for a winner. The site will be hosted on a Rackspace Cloud Server ... |
Why having a valid certificate for "exampe.com" I can't make a "child" certificate for "subdomain.example.com"?
What insecurities will arise if browsers start allowing domain's certificates to be valid CA for subdomains?
|
I'm creating a contest that will allow users to login using their Facebook & Twitter accounts and submit votes on videos. My clients concern is that users will game the system by logging into different Facebook & Twitter accounts to keep spamming votes on the same video.
How can I prevent this type of voter fraud?
|
I recently made a complaint to a company about them sending out passwords in plain-text via email upon registration knowing that it is a potential security risk.
One of their employees responded with the following:
The security depends on the strength of your email password. This is the default in the billing system -... |
Corporate policy only allows users to connect corporate-issued machines to the network managed by Active Directory. Is there some means to log or otherwise detect when the same user account joins the domain with "unauthorized" machines? Suppose the user connects non-simultaneously and can rename their machine to match ... |
I need an advice. I have a communication protocol using 3DES cipher.
Each time the client connects (and it can be very often like 1-10 per second), the 24-byte key is generated randomly on server side, encoded by XORing with some static 24-byte password (quite complicated, not many repeated bytes) and then sent to the ... |
The SEC allows for individuals to not register with them if they don't permit business with users outside of the state:
A broker-dealer that conducts all of its business in one state does
not have to register with the SEC. (State registration is another
matter. See Part III, below.) The exception provided for intr... |
I'd like to know if there is any danger of someone being able to access the database via XSS vulnerabilities on this page.
I have the following link. When you go to this link, the text I've enclosed as code displays on the site:
www.site.com/languages.php
{"languages":"
\n
<\/a><\/div>\n
English<\/div>\n <\/div>
\n
<\/... |
We have a Drupal application developed for sharing files.
We are allowing zip files to be uploaded by logged in departmental user.
We are using Drupal private file system (outside webroot).
We are using php Fileinfo for validation.
Only logged in user will be able to download the file.
Now our security team is not al... |
I am working on an ASP.NET MVC web application, which fetches its data from an API in the back. So authentication is currently done via ASP.NET Forms Authentication, which means the client sends email and password to the website, the website transfers that data to the API which returns an authentication token, which is... |
I am currently looking into authentication protocols which work well with REST API, in java.
There is something fundamental I don't understand: I read a lot of material about OAuth protocol, SSL, basic HTTP auth, digest etc.. And in all of them there are apparently different meanings of the term "client". In most, from... |
I have a web service built with WebAPI that accepts JSON requests and responds accordingly. The core architecture is built but there isn't any authentication/authorization.
After a lot of googling and poking around sample projects, I'm not sure where to start. I've found a ton of material from 2008 and 2009 but not... |
Imagine a service that makes sensitive information available under a secret URL via HTTPS only, without requiring any other authentication. In fact, these are already widespread.
What level of security does this offer, compared to, say, a traditional HTTPS login form using a username/password that's saved in the browse... |
I have a problem I'm hoping someone could help with regarding the use of UNION SELECT, in a scripted/automated way to find columns that are exploitable (having already found the number of columns using ORDER BY)
Doing this manually
Using http://www.site.com/index.php?id=-2 UNION SELECT 1,2,3,4,5,6,7,8-- I am aware I ca... |
If I encrypt the same file twice with GnuPG, using the same key, will I get the same result? or is it using some random/psudeo-random segment to improve security like rsynccrypto?
|
So, when i do an online payment transaction i "sign" my transaction with my digipass using some sort of a MAC (HMAC) with a shared key and some information that is unique for this transaction.
But using this scheme, how can a bank "proof" later (in court for example) that you did this tranaction? The bank has to store... |
First off, before I ask my question, let me explain what I am NOT asking. I am NOT asking for a way/method to reverse a hash output; by definition, a hashing function is one-way.
Is there such a thing as an inverse hashing function? I am likely calling it the wrong name. What I mean is a function where, for example, if... |
I have two disks. They're both bootable and run Linux.
When I physically mount the disks, I can see scsi devices get added. /dev/sdb and /dev/sdc. However the partitions are not detected. I can't see for example /dev/sdb1. It seems like someone has gone into a lot of effort to hide the partitons but I don't know how.
I... |
I am developing a webapp that does not reveal record count, because it hides the primary key. I am looking for a better way to do this.
My favorite idea is to encrypt the ID itself with a block cipher, because that would require not additional tracking tables, and if the block size is equal to the key size, it should w... |
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