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 estimate the time needed to crack RSA encryption?

How to estimate the time needed to crack RSA encryption? I mean the time needed to crack Rsa encryption with key length of 1024, 2048, 3072, 4096, 5120, 6144, 5120, 7168, 8192, 9216, 10240, 11264, ...
19
votes
5answers
3k views

What's the practical limit for rainbow-table based bruteforce?

Say we have a hash of a password. The password can be considered to be made of of totally random characters and has a fixed length of N. The hash is SHA1(password+salt), where the salt is of length M. ...
50
votes
8answers
78k views

Where can I find good dictionaries for dictionary attacks?

I’m wondering where I can find good collections of dictionaries which can be used for dictionary attacks? I've found some through Google, but I’m interested in hearing about where you get your ...
21
votes
5answers
2k views

Do non-keyboard characters make my password less susceptible to brute forcing?

I can put characters in my password for which there are no keys on a keyboard. On Windows, Alt+#### (with the numpad) inserts the character for whatever code you type in. When I put this in a ...
-1
votes
1answer
5k views

Has the WPS brute-force cracking issue been fixed?

I have heard a rumor that the WPS brute force attack doesn't work on newer devices, and that you now have to try all 10^7 PINs to find the correct one. Is that true?
20
votes
4answers
9k views

how long does it take to actually generate rainbow tables?

I've been reading up about rainbow tables as I think they're quite interesting cause they're actually a pretty simple concept. Anyway, I was wondering, has anyone been involved in actually generating ...
10
votes
1answer
11k views

Brute Forcing Password to a Truecrypt-encrypted file with Partial Knowledge

A while back, I encrypted a few files with Truecrypt, and stored the password in my head. Now I need to access it again, the password isn't working. I'm sure most of it is right, but I'm off by one or ...
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 ...
18
votes
7answers
14k views

Invalid users trying to log in to my server

I'm seeing a lot of log entries that appear to be failed login attempts from unknown IP addresses. I am using private and public keys to log in with SSH but I have noticed that even with private ...
14
votes
2answers
912 views

Are there some good papers (or discussions) on using Markov chains or Hidden Markov Models for password auditing/cracking?

As a programmer and language enthusiast I've been very interested in Markov chains for some time. Considering the influence of natural language on password and passphrase selection (by humans of ...
8
votes
1answer
329 views

General purpose slow/unique hash routine for dup checking of private data, without storing the data itself?

I am wondering if there is a percentage of uniqueness known to be lost with every repeat of various hash routines, like MD5, SHA1, and how that might compare with other algorithms. If theoretically I ...
5
votes
1answer
9k views

Is my router vulnerable if WPS is enabled but WPS pin code is disabled?

I was reading about Reaver and wi-fi protected setups (WPS). In my Netgear router I have the option to disable the WPS pin code, but still have the WPS push button enabled. Am I secured with such ...
4
votes
2answers
857 views

Web & insecure HTTP - Using RSA for encrypting passwords on the client side

I used client side password hashing in my register and login project. Its purpose is to prevent passive adversaries/eavesdroppers from discovering users' plaintext passwords when HTTP requests are in ...
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 ...
32
votes
4answers
17k views

Are salted SHA-256/512 hashes still safe if the hashes and their salts are exposed?

Scenario: a database of hashed and and salted passwords, including salts for each password, is stolen by a malicious user. Passwords are 6-10 chars long and chosen by non-technical users. Can this ...
19
votes
10answers
4k views

Best password strength checker

In XKCD #936: Short complex password, or long dictionary passphrase? Jeff claimed that password cracking with "dictionary words separated by spaces", or "a complete sentence with punctuation", or ...
15
votes
8answers
907 views

Bruteforce vs Denial of Service

I had a problem presented today which I found quite interesting. You have an application with a management panel. You know some of the accounts as they are standard. You want two things: You want ...
12
votes
1answer
279 views

What's an attack's 'computational complexity'?

I'm writing a business-language report about MD5. In my search a found a paper by Yu Sasaki and Kazumaro Aoki explaining their 2123.4 pre-image attack on MD5. I know that it has something to do with ...
8
votes
8answers
2k views

With which algorithm I can prevent a brute force on a login?

I want make my software more secure. I want prevent it from brute force attack. I know that a strong password is the best but I can not control it. The algorithm must scale from a very small system ...
6
votes
4answers
1k views

Password entropy in layman's terms

Entropy is a term used often in relation to password security and brute-force attacks, but it is a topic that can get complicated quickly. What is the best way to describe password entropy (what it is ...
8
votes
3answers
1k views

time to crack file-encryption password - more than just iteration

I have often seen that takes x amount of time to crack a certain length password. But this just seems to be the amount of time it takes to iterate through all the possibilities. What about the time it ...
4
votes
4answers
2k views

Are there lists of most common words or ngrams used in passwords and passphrases?

I've been thinking about ways to focus brute forcing dictionary attacks on passwords and passphrases based on the assumption that certain words, combinations of letters, and combinations of words are ...
4
votes
4answers
4k views

Brute force vs other methods of recovering passwords from shadow file

Do you know any good approach for de-hashing/actually bruteforcing hashed passwords in the shadow file? On various operating systems, any good solutions/methods/programs. Or is it better to upload ...
10
votes
2answers
7k views

Why does Hydra return 16 valid passwords when none are valid?

I've been playing around with Hydra and DVWA and I've hit a bit of a snag - Hydra responds letting me know that the first 16 passwords in my password list are correct when none of them are. I assume ...
6
votes
3answers
798 views

Attack vectors for brute-forcing website passwords

When talking about password security, a lot of discussion centers on the risk of a password being guessed in a brute-force attack. For websites where a user has registered an account, what are the ...
5
votes
3answers
12k views

Bruteforce on 10 characters length WPA2 password

I'm trying to hack my own WPA2 network for learning purposes. I have the *.cap file generated by aircrack-ng tools after a WPA handshake. I've tested by including my own password and a bunch of ...
3
votes
1answer
377 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 ...
3
votes
1answer
20k views

How long to brute-force WPA password?

Bob has a password (for his WPA encrypted wifi) which is 8 characters, all lowercase, and not a dictionary word. Eve lives next door to Bob and wants to illegally hack his WPA. The number of ...
9
votes
4answers
496 views

Are there state-of-the-art techniques or theory specifically for attacking passphrases over passwords?

With passphrases becoming more and more common based on length being more important than complexity, I'm assuming there must be some work going on involving techniques aimed specifically at cracking / ...
4
votes
4answers
926 views

How unlikely is it that a Google Doc link is guessed?

Most (if not all) of us know that a Google Doc link looks something like this: https://docs.google.com/document/d/13P3p5bA3lslqEJT1BGeTL1L5ZrQq_fSov_56jT9vf0I/edit There are becoming several tools ...
4
votes
4answers
1k views

Brute-force heuristics used in password cracking

Existing questions on this site discuss some of the heuristics used by password cracking tools to avoid doing a completely naive brute-force search (for example, "dictionary word with number ...
3
votes
2answers
560 views

Automated URL Discovering

I built a simple server containing static files at /files/ and I'm attempting to discover them using automated tools. I'm using wfuzz to brute force on the URL but is that the only way? Is there any ...
3
votes
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 ...
2
votes
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 ...
2
votes
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 ...
1
vote
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 ...