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.

learn more… | top users | synonyms

0
votes
0answers
20 views

Cracking a 6-character alphanumeric password Windows dialog box

To put this problem in context, I have a touch monitor screen whose firmware program is protected by a password. The firmware program is downloaded over RS232 via a Windows utility program provided ...
2
votes
4answers
121 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 ...
-4
votes
0answers
30 views

How to set a hydra http-post-form attack for this router login site? [on hold]

I'm trying to use hydra to crack it's password but don't know how to set a http-post-form attack! It's a router login websiteit which has 8088 port open.Can't do a ssh, ftp, or http-get,only ...
0
votes
2answers
69 views

Showing CAPTCHA

I'd like to show a CAPTCHA to prevent brute forcing attempts, but I was thinking of showing it whenever a user fails for an invalid username/password combination after X attempts, regardless of ...
1
vote
2answers
154 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 ...
1
vote
1answer
127 views

Cracking MD5 passwords with the same salt

How long would it take to crack passwords up to 10 letters long if you knew the hashes were MD5 with a salt (that you know)?
0
votes
2answers
96 views

How long would it take to bruteforce an AES-128 protected pdf knowing the key is 20 letter long and that the charset is A-Z,0-9?

The question says everything, knowing that a pdf is protected using standard Adobe password encryption that comes with Acrobat Pro (which as far as i know is AES 128) how much would it take to ...
1
vote
2answers
63 views

Are repeating random patterns weaker than non repeating random patterns?

Which would be harder to crack: a password comprising of n characters randomly selected or a password comprising of x randomly selected characters repeated m times so that m*x=n. For example: ...
0
votes
1answer
196 views

Cracking a web form based logon with hydra [closed]

How do I have to use hydra on a web form? What I have done so far: I already successfully used hydra on a folder with an HTTP authentication: http://localhost/test/authtest/ with user admin and ...
3
votes
3answers
81 views

Is login limiting still needed if we employ multi-factor authentication?

The status quo is that most online websites limit login attempts per IP address, or even per account since some attackers possess huge amounts of IP addresses. OWASP declares: When multi-factor ...
3
votes
4answers
183 views

Ethical brute force demo on a web login when knowing the password complexity requirements

We are currently having accounts compromised at a substantially high rate. Some in the organization believe that our password complexity requirements is enough to thwart brute force attacks. I wanted ...
0
votes
0answers
54 views

My server has been brute forced what now? [duplicate]

I have installed a raspberry pi for fun at home. I opened the port 22 and this morning I was concerned about someone brute forcing my server. I ran this query : cd /var/log;zgrep ssh auth*|grep ...
1
vote
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: ...
0
votes
1answer
54 views

Find hash-function if original and hash are given? [duplicate]

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 ...
0
votes
1answer
119 views

How do we estimate the time taken to crack a hash using brute force techniques

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 ...
3
votes
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 ...
2
votes
1answer
231 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: ...
0
votes
0answers
96 views

Testing Basic Authentication with ncrack

I'm conducting some basic pen testing against a page protected with Basic Authentication. I've sucessfully tested with Medusa and Hydra but am struggling to get the syntax correct for ncrack. the ...
1
vote
2answers
125 views

How to make an efficient bruteforce attack on Windows? [closed]

I've been trying to figure out a way to efficiently bruteforce on Windows, but the method I currently have isn't very efficient. I did some profiling and found out that on average it can go through ...
0
votes
0answers
200 views

Brute-Force/Dictionary attack against encypted file using PBKDF2 key derivation

I have been following this very useful post by Thomas. My use case is slightly different. I am developing a mobile application which requires some sensitive data to be stored on the device in a SQLite ...
1
vote
1answer
70 views

Can Hydra crack a flash-based login?

Is it possible to brute force a flash login with hydra? If not, what is a good tool to pen test a flash login?
6
votes
1answer
194 views

Harden a server against mass SSH DoS attacks

How can a Linux server be protected against an attacker that tries to open a large number of SSH sessions (probably trying to brute force a password) that no ports remain to be able to legitimately ...
1
vote
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 ...
-3
votes
1answer
44 views

How many possible symbols and punctuations in a password? [closed]

I want to compute the possible combinations of a password consists of 8 digits of: alphabetical letters (26), numbers (0-9), symbols and punctuations. In order to compute this, I have to know the ...
2
votes
1answer
108 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 ...
1
vote
1answer
102 views

Username Enumeration as a Threat

I have found a Username Enumeration Vulnerability through which I am able to determine whether a particular user is registered with that site. While trying to brute force, after 5 attempts it asks for ...
2
votes
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 ...
0
votes
2answers
78 views

How do you overcome the problem of the salt being public and known by the attacker? [duplicate]

I believe that when adding a salt to the password you need to store the values so you can compute the hash again. But, what does happen if the attacker get the salt? How is it possible to add value ...
0
votes
1answer
42 views

Does restarting an encrypted session increase security and deter attacks?

When a user initiates a SSH connection for example, keys are exchanged and a session is established with a new "passphrase" each time. If an attacker were to attempt to brute force this connection, ...
1
vote
1answer
863 views

Forgot password to 7-Zip archive

I think I already know the answer to this question, but I thought I'd ask the experts anyway. A few months back, I created a password-protected 7-Zip archive which housed the source code of a simple ...
1
vote
1answer
308 views

Hydra gives wrong passwords

I've been trying to use hydra (educational way) but with no success. The site method is http-post but performed by ajax (should it be a problem? I think not). After execute the command I got an output ...
0
votes
1answer
56 views

Is encryption less resistant to brute-forcing compared to hashing?

I understand that a hashing algorithm like bcrypt uses several rounds of hashing to make it computationally expensive for a brute-force attack. How does encryption work against a brute-force attack? I ...
1
vote
2answers
138 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 ...
3
votes
3answers
242 views

Could using a generated key from an online service be considered a risk?

With some colleagues we're having a debate regarding the randomkeygen.com website. I do think that there is a security risk using the generated keys of this (or any of this kind) website. Why ? ...
0
votes
1answer
72 views

What is the best way to generate a password/pin like string using brute force method? [closed]

I have a string of 7 characters. I'm supposed to generate all the combinations. But some combinations are more likely than others, I would like the more likely ones to be generated first. If I ...
1
vote
1answer
259 views

Distributed IMAP-Dictionary-Attack-Tool?

I have a client with a hacked IMAP-Account, and the attacker(s) made thousands of password-attempts, probably with a fixed set of passwords, from different IPs before they got in. After successful ...
1
vote
0answers
1k views

BruteForce on Hydra (Usernames or Password with Special-Chars), letter “Ñ”

I use Hydra with the Web-Form (Http-Post-Form); and I'm trying to use a list of Usernames when some of the nicks contain a letter ñ. For example I have the following account in my list: Username: ...
15
votes
3answers
2k views

Why check to see if a password is already used by another user?

This is coming from a joke originally in French: Enter your password. carrot Sorry, your password must be more than 8 characters. carottegéante (giant carrot) Sorry, your ...
-1
votes
1answer
1k views

Hydra bruteforce is giving wrong passwords. Can't seem to work any help? [closed]

Ok so what im actually trying to do is to bruteforce my own account on some website just to check myself . This is NOT for illegal steps or use , im trying to crack my OWN password , and im trying to ...
1
vote
1answer
110 views

What is the strength of the key derivation function on Android device encryption?

What is is strength of the key derivation? Specifically, how many milliseconds or microseconds would it take a desktop computer to check a guessed password to see if it is a match? I am aware this ...
4
votes
3answers
197 views

Is there any reason in particular encryption keys aren't arbitrarily large?

It's my understanding that the more bits an encryption key has, the longer it takes to break the encryption. What is the down side of having a larger encryption key or why don't we see keys of size ...
0
votes
1answer
129 views

How can brute force scripts tell once they're found the correct key?

If you have a random block of data and you encrypt it with a key, how can a brute force script tell when it has found the correct key? Is it possible without some sort of reference to the original ...
4
votes
4answers
407 views

Can't brute force password cracking somehow be throttled?

Online articles mention the importance of a strong password and suggest that hacking tools allows bad guys to attempt millions of passwords per second. I am wondering why OSes and websites and such ...
0
votes
1answer
751 views

Hydra gives wrong answers

Problem: Hydra keeps giving me incorrect passwords every time. I'm using brute-force via Hydra to guess the correct password on a certain website. First of all I used BurpSuite to intercept the page ...
1
vote
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?
1
vote
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?
8
votes
2answers
4k views

What's the purpose? Strange login attemps “sshd[***] Received disconnect from **.**.**.**: 11: Bye Bye [preauth]”

I've seen something like: sshd[***]: Invalid user oracle from **.**.**.** // 1st line sshd[***]: input_userauth_request: invalid user oracle [preauth] // 2nd line ...
2
votes
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. ...
2
votes
3answers
314 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 ...
3
votes
2answers
136 views

How can you I detect low frequency brute forcing over multiple connections?

While I realize that servers can easily detect brute forcing strategies via a single I.P, it seems that servers would be vulnerable to a distributed attack from a botnet, with each computer attempting ...