An attack using every possible input to attempt to produce the correct output. Typically the method of last resort when no weakness allows the use of a more restricted input set. E.g. trying all possible (or likely) passwords, in an attempt to guess the correct one.

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How to optimize compressed file cracking?

I'm currently doing research on cracking encrypted, compressed files (specifically: uif, zip, 7z, dmg). Looking at all the utilities out there, it seems the time it takes to crack something is ...
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4answers
326 views

Can I brute-force a password hash even if I don't know the hash-algorithm used?

Can I brute-force a password hash even if I don't know the underlying algorithm? For example if I get hold of a database with password hashes and the used hash algorithm is unknown, like a random ...
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2answers
16k views

How to setup GPU for Cracking WPA/WPA2?

I have a Dell N5110 15R Laptop that I'm planning to use for GPU based cracking of WPA/WPA2 passwords. The thing is, I'm not a really big fan of password dictionaries and rainbow tables, I'd rather ...
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1answer
378 views

Non English password dictionaries

What is a good resource for wordlists used in auditing passwords in non english languages. I have extensive wordlists in English ranging to several GB's, but can't find similar resources for other ...
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281 views

Can an attacker guess my password length from a hash? [duplicate]

Possible Duplicate: Possible to detect password length from hash? Is doubling your password adds more security? Considering I do not provide him any personal information relating to it, are ...
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3answers
316 views

Is there an internal equivalent to fail2ban?

fail2ban is a protection against brute-force that locks a user out after a definable maximum failed login-attempts. But if a user already has access to a server with another username already fail2ban ...
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2answers
4k views

Is it possible to brute force all 8 character passwords in an offline attack?

This article states: Brute-force techniques trying every possible combination of letters, numbers, and special characters had also succeeded at cracking all passwords of eight or fewer characters. ...
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3answers
1k views

what is the fastest and cheapest way to crack this kind of hash - md5(md5($password) + salt))?

I'm looking for a program that can use any GPU (ATI\NVIDIA) and can brute force a vBulletin hash - md5(md5($password) + salt)). I have the salt and hash. the password contains the symbols - ...
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1answer
640 views

What are realistic rates for brute force hashing?

I'm trying to gauge password strength assuming that the attacker has a hash of my password. Can anyone cite some realistic contemporary rates at which someone could perform various hashes? I know most ...
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2answers
203 views

Slow down symetric encryption

I'm developing a program in Java. In one step data should be encrypted and exported in a file. As of now we are encrypting in AES-256 I want to slow down a possible brute force attack as much as ...
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2answers
326 views

Seeking advice on how to build a box to brute force hashes? [closed]

I work in a startup security firm, and I need to build a GPU-based to brute force password/hashes, which can be used to validate password strength and test hashing algorithms. I expect some high ...
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4answers
15k views

How to generete dictionary for brute force attack?

I need to crack my own password. Advantage is that I know possible characters and maximum length. What I need is to create dictionary for brute force attack. Dictionary should contain all the combos ...
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1answer
3k views

How long it will take to crack a RAR password?

I wonder how long it will take to crack 16 character alphanumeric WinRAR password for a mini supercomputer. As far as I know graphic cards are preferred over CPUs to crack passwords nowadays. If we ...
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3answers
3k views

How should I defend against TightVNC brute-force attacks?

How should I defend against this type of attack? This is a tightvnc logfile excerpt from a linode cloud server running Ubuntu 12.04 (Precise) with the ubuntu-desktop package added to the bare server. ...
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4answers
128 views

Does it take longer to brute force a password starting with z than one starting with a?

I was wondering about the following: If someone tries to get my password with Brute Force, will a password starting with "a" guessed faster than one starting with "z" ? In this case assume the ...
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2answers
142 views

Slowing down repeated password attacks

I've been reading suggestions to use time-consuming formulas for checking passwords from login attempts, so that repeated attacks will be slowed down. Wouldn't it suffice to just sleep a bit in the ...
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2answers
483 views

Is a password easier to brute force if it contains a repeating pattern?

My question is different from this previous question: Does repeating one word to form a password result in a similar pattern in its encrypted format?. I'm specifically wondering about brute force ...
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2answers
1k views

how long does it take to brute force varying encryption standards?

Let's say I want to encrypt information in a database. What would be the best encryption algorithm to use and why. I was thinking AES, since it's widely used as a government standard, but if the ...
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3answers
475 views

Why are MD5 collisions dangerous?

I understand that the MD5 algorithm isn't collision resistant, and that collisions between data of arbitrary size can be found with more efficient methods than brute-forcing. However, I have read ...
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1answer
1k views

Brute-force a passphrase, generated by `pwgen 16 -s`, of a GPG CAST5 archive

A sad story: One of our hard drives failed. While it was failing, we managed to take a quick backup. As it is our standard practice, we encrypted the backup using GPG (by however method Duplicity uses ...
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2answers
2k views

How do you bruteforce decrypt data if you don't know what you are looking for?

If I wanted to brute-force decrypt data, I would try decrypting it with a key and see if the decryption returned nonsense. If the decryption returned meaningful data (ex. something that a natural ...
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1answer
1k views

Brute-Force GPU Password Crackers

Brute-force password cracker programs which claim GPU support include John the Ripper, ighashgpu, oclHashcat, and others. oclHashcat appears one of the more popular, but I am not sure which AMD/ATI ...
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2answers
178 views

Cloud services - A window to outsourcing illegal activities?

Recently I was exposed to a number of stories where alleged illegal activities (for this case, we can take brute-force) are outsourced to the cloud, and are run by the cloud providers. The providers, ...
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1answer
747 views

Pen test cell-phones

A customer has asked to conduct a pen-test on the phones of employees. The target is text messages in the phones. Text messages are stored on the SIM for security reasons. Physical access to the ...
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1answer
232 views

Hydra bruteforce and JSON

I am having problems with Hydra and a JSON payload. The login request (intercepted with Fiddler), is the following: POST http://architectureservice.test.com/api/v1/login HTTP/1.1 Host: ...
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1answer
102 views

Given a hash, salt, charset and password length, how do you get the password without brute-forcing it?

I got that question on an exercise and I'm not sure what to answer. Without conventional brute-forcing and without a rainbow table, how could I find out the password? An improved brute-force ...
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3answers
2k views

How can I generate custom brute-force dictionaries?

I have found during testing that companies often use variations of their names for critical passwords (for example Microsoft's password might be M1cr0s0f+ or m1cros0ft etc etc). So if I gave it the ...
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1answer
547 views

How large RSA-keys could the worlds combined computer power factorize in reasonable time?

If you combined every microprocessor on earth into one humongous computational cluster, how large RSA-keys could you factor in reasonable time (lets say a few years)? I know from reading the answers ...
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2answers
181 views

ASLR in Ubuntu 11.10

In many of the exploits I see nowadays, brute forcing is a common method of bypassing ASLR on 32 bit machines. However, many of these exploits crash the current process, for example, PHP. Isn't the ...
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1answer
109 views

Better than brute-force way to find the “lowest” sha1 hash?

While pointing out a SQL injection flaw on another question, I was able to show that an arbitrary sha1 hash could be inserted into a query such that it would be taken for a real hash, and was ...
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3answers
24k views

Wordlists on Kali Linux?

I notice that in /usr/share/wordlists in Kali Linux (former Backtrack) there are some lists. Are they used to bruteforce something? Is there specific list for specific kind of attacks?
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1answer
320 views

Use brute force to mitigate brute force

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 ...
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2answers
432 views

Known password length, brute force character in place?

We all know that brute forcing is a very slow process and trying all unnecessary possibilities is dumb. By knowing the password length, we can skip trying possibilities of other password lengths and ...
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5answers
290 views

Is there something similar to DNSBL's for protecting against forceful browsing?

I want to protect a couple of Apache webservers against forceful browsing. Lately there have been multiple scans querying for non-existent applications on them like phpMyAdmin, notably known for their ...
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3answers
1k views

What utilities exist to brute force a username and password?

I'm trying to persuade management to purchase two factor authentication for securing VPN and terminal server access. I've made significant progress by demoing TSGrinder, but would like to list other ...
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2answers
156 views

In what situations can a hacker try to break passwords millions of times? [duplicate]

I keep reading about situations where a hacker could "easily" brute force a password (most recent example) but I'm confused about when some has an opportunity to do this kind of thing. If it is a ...
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1answer
533 views

How bruteforce works code wise

I was wondering how bruteforce methods work from a code level. How does the code get access to a login page for example and insert information into the necessary fields? And is the code able to ...
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4answers
691 views

Our logs showing a lot of SSH brute force attacks originating on Port 11

this forum has been brilliant so far. Just wondering if I can get a bit more help: Can I get some info on a large amount of SSH brute force attacks originating from port 11 on the external host over ...
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3answers
251 views

Brute Force In Order Or Random?

Which is faster, on average to find the original plain text of a hash: brute force in-order, or with random plaintexts?
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2answers
723 views

Password Protected Zip: if attacker had one file, can use it to decrypt all files?

Consider a folder containing the following files: (file1.txt, file2.doc, file3.pdf) all zipped and password protected, if attacker had one of these file, can use it for decrypting all without knowing ...
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2answers
417 views

Brute force a GUI login?

I know I have read somewhere that the reason the UAC prompt in Windows 7 was employed is that viruses that would supposedly execute privileged instructions won't be able to "click" the confirm button ...
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1answer
174 views

Stripping / appending characters from user password before hashing to conceal it forever?

I had this idea to permanently conceal user password by requiring minimum length then stripping certain characters. For example if the user password is secret123, the system will strip it down to ...
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3answers
104 views

Touch tone phone username and password

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: ...
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1answer
89 views

Is there an equation to calculate the number of instances of a series of characters exist in a given key space?

If I'm using 16-18 character-length passwords with 94 different possible values-per-character (lower alphas, upper alphas, numbers, and special characters), is there an equation I can use to calculate ...
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2answers
140 views

How do you know if blowfish key is correct?

Encryption novice here so maybe this question makes no sense... Obviously if you know what the clear text is and it decrypts right, you have it. But if someone is running through keys to break the ...
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1answer
128 views

Botnet Attempting to Login to Website

Our server has recently become a target of what appears to be a botnet attack. The first indication was an insane amount of traffic to one of our client's websites - so heavy that the server entirely ...
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1answer
1k views

How many possibilities can today's computers check (per second) in a SHA512 hash of a 50-byte-long random entry? [closed]

The problem I want to avoid is "brute force" attacks against a database. So if I add a 50-byte-long cryptographically random salt to my information (which I don't need to retrieve, just its hash) - is ...
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2answers
2k views

Computing RSA 1024-bit Decryption Performance [closed]

I want to be able to tell how many keys per second, using RSA 1024-bit keys, can be checked on a standard Pentium 4 system. How can I use this to determine decryption performance, and possibly ...
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2answers
426 views

Hash, encryption of file… key? Need help [closed]

So my previous question was with some help on pcap files as I am doing a security course and we have a challenge to figure out what was going on in our network. Now one of the files I retrieved is an ...
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3answers
266 views

Mass account lockout prevention using CSRF tokens

I'm currently working on reducing the risk of mass account lockout on a site that (unfortunately) issues sequential, numeric user IDs. Changing the structure of the userID is not an option at this ...