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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9
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2answers
6k views

Why limit passwords to ascii printable characters? [duplicate]

Possible Duplicate: Do non-keyboard characters make my password less susceptible to brute forcing? Every article on password security that I read tells people to make the password more ...
5
votes
2answers
8k views

Can DES-based hashed password be recovered if salt is known?

Can a hashed password be recovered if the hashing is done with DES based crypt function in PHP and both the hash and salt are known by the attacker? Consider the following example: $salt = 'mysalt'; ...
3
votes
1answer
2k views

Will using unicode chars in my password increase security? [duplicate]

Possible Duplicate: Do non-keyboard characters make my password less susceptible to brute forcing? Bruteforce tries cracking the hash with every possible combination of letters. Then, If ...
42
votes
4answers
31k 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 ...
31
votes
8answers
5k 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 ...
45
votes
4answers
66k views

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, ...
5
votes
4answers
214 views

software to keep a list of IP that try to access ssh over a set of rules and feasibility

i'm interested in software or set of scripts to keep a lists of filtered IP that attempt to brute-force ssh, and to label an IP as brute-forcing i would add some checks like: one attempt to log as ...
12
votes
4answers
764 views

How should I secure a contact form that appears on every page of a website?

My client has a small "Contact Us" form on every page of their website. They are adamant about not including CAPTCHA verification on these forms, to keep them easy to use, but I feel it is my ...
9
votes
1answer
208 views

Long running SMTP session

I recently noticed an SMTP session on my server which started when a remote host connected but never seemed to result in any emails being delivered. I could see that it was probably a SPAM site and so ...
3
votes
3answers
447 views

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 ...
8
votes
3answers
2k 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 ...
23
votes
4answers
16k 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 ...
5
votes
4answers
5k 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 ...
7
votes
5answers
1k views

Are there any security measures that are resistant to a brute force attack?

I'm not talking in particular about encryption, but security as a whole. Are there any security measures that can be put in place to protect data and/or a system that can withstand even a hypothetical ...
2
votes
1answer
860 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 ...
19
votes
4answers
5k views

Protection against account lockout DoS

Any ideas on how to protect against the following scenario? Company x uses active directory for authentication of it's employees. The company has multiple authentication points that are semi-public ...
95
votes
9answers
188k 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 ...