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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5k views

How do i brute-force an SSH-login which has an only 4-letter password?

Suppose, you know that a certain computer is only protected by such a short password, then you could just try every possible combination easily. How would a script look like, that tries to crack that ...
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1answer
4k 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?
3
votes
2answers
124 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 ...
2
votes
3answers
1k 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 ...
1
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4answers
9k 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 ...
2
votes
2answers
132 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 ...
2
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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 ...
29
votes
5answers
2k views

What are the security implications of storing password blacklist?

I want to add a password blacklist that would prevent the 1000 most common passwords from being used in order to mitigate shallow dictionary attacks. Is there any negative implication of storing this ...
3
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2answers
382 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 ...
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1answer
440 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 ...
44
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8answers
65k 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 ...
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1answer
542 views

LophtCrack version 6.0.12 is not auditing my Administrator password [closed]

I am using LophtCrack on my Windows 8 OS. I was testing my password strength and the problem I am seeing it is not working. It doesn't reveal my Admin password, I've run the process for half an hour. ...
4
votes
2answers
1k views

Faster methods for decrypting a TrueCrypt disk, esp. knowing the algorithms used

I encrypted (with TrueCrypt) all my hard drives and had the passwords stored in an encrypted file on my USB disk. The passwords are all (except one) 50 character randomly-generated ciphers, there's no ...
3
votes
3answers
860 views

Avoiding Brute Force Attacks in a Web Based Login Form

My login form uses Ajax so it doesn't need to reload if the password is wrong. A PHP script process the request and creates the session if the credentials are right. My idea is to have the PHP script ...
2
votes
1answer
442 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 ...
3
votes
2answers
698 views

Failed RDP brute force attack from Microsoft IP address?

I use RDPGuard on my webserver. I have noticed that it blocked an IP address which seemed to originate from a Microsoft registered IP address: Process Information: Caller Process ID: 0xf78 Caller ...
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2answers
1k views

Can the U.S. goverment crack encryption? [closed]

Does USA government have the sufficient processing power to crack keys in matter of seconds? Let say 2048-bit RSA, for example. Since the RSA algorithm was developed by USA government (NSA?), I ...
2
votes
3answers
396 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
399 views

Feasibility of brute-force on online password [closed]

I am familiar with how offline brute-force attacks work. But for online accounts, assuming no social engineering, how feasible is it to brute-force attack a password? For example, is this dependent ...
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votes
1answer
631 views

How long does it take to crack a 100-letter long winrar password? [closed]

i´m interested in how long time it would take for a super computer dedicated to crack to crack a 100-letter long winrar password. The password contains Lowercase, Uppercase, Digits, ...
6
votes
3answers
679 views

Can I spoof IP addresses when attempting to brute force a login?

I am testing my website with hydra brute-force software. But accessing my apache conf remote server file, it seems that an attacker can't log-in more a limited number of times per seconds. Does hydra ...
9
votes
1answer
237 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 ...
4
votes
1answer
278 views

WPA2 audit tool

For the purposes of my own research, I have a very modest budget to set up a modest WPA2 brute-forcer supported by GPU(s). I've done some homework: Brute-Force GPU Password Crackers How to setup ...
0
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0answers
31 views

How can I determine the encryption used by knowing input and result? [duplicate]

Is it possible to determine the encryption or hash used if I know the original input and final output? There is a similar post here: Determine encoding/hashing methods used based on knowing the input ...
4
votes
2answers
5k views

Estimated cost to make a brute-force WPA2 attack feasible

It's been shown that a brute-force attack on WPA2-Personal is possible in a reasonable amount of time. These successful attacks appear to be limited, however, to researchers who have the budget to ...
2
votes
1answer
943 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 ...
0
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2answers
312 views

Bruteforce Passphrase of Dictionary Words

Consider the all lowercase passphrase: "lazy fox haggles treaty" Assume all four words are in a dictionary of 2000. Bruteforcing word combinations, how long does it take to crack this password at ...
5
votes
2answers
577 views

Do SSD's offer significant performance boost for Scrypt?

Being a memory intensive hash, I was wondering if SSD's offer any appreciable performance boost for brute force attacks.
1
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1answer
444 views

Brute Forcing Domain Controller

I have a MS-Server2K3 domain controller that also serves as a Exchange server. Due to recent network speed loss and issues I began looking at event logs and noticed an exceptionally large number of ...
4
votes
1answer
126 views

Could a password hash that's prone to more collisions provide better overall security?

Website security breaches seem to be a common occurrence, giving the attacker password hashes that he can conduct a brute force attack against, often given him a list of passwords that will work on ...
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votes
3answers
7k views

How long will it take to crack a 10-15 character winrar password? [closed]

Ok, long story short, I'm currious how long it would take an agency to crack a 10-15 character winrar password. The file names in the archive are also scrambled including a word at the start and ...
4
votes
2answers
734 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 ...
2
votes
1answer
464 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 ...
12
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3answers
4k views

Cracking MS-CACHE v2 hashes using GPU

As most people here will know, Windows caches domain/AD credentials in a format known as MS-Cache v2. Obviously, these would be excellent passwords to gain during a penetration test when local access ...
1
vote
1answer
124 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 ...
1
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1answer
294 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 ...
2
votes
1answer
2k 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 ...
3
votes
2answers
422 views

How can i calculate the number of possible passwords?

I have found a flaw in a site where the password reset feature resets passwords in the following format UpperCaseLetter-Number-LowerCaseLetter-Number-LowerCaseLetter-Number-UpperCaseLetter ...
12
votes
2answers
489 views

Zip file with two password

I used this command to password protect a zip file on Linux : zip -P 9000 hash.zip hash.py and it creates the zip file just fine, then I wrote a program to test every possible password on it from 1 ...
12
votes
2answers
8k views

Why are GPUs so good at cracking passwords?

What is it about GPUs that lets them crack passwords so quickly? It seems like the driving force behind adopting good key-derivation functions for passwords (bcrpyt, PBKDF2, scrypt) instead of ...
10
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4answers
416 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 ...
1
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1answer
413 views

Pointers for john the ripper rulesets

I've been pouring over the JtR ruleset documentation and making little progress. I understand how to use it to make various permutations from a given wordlist, that's fine. However, I'm trying to ...
1
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2answers
643 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 ...
4
votes
3answers
318 views

Hashing a key: less entropy than the key itself

A web API needs to store a 'key' for authentication, in much the same fashion as a password but at 128 characters. My concern is that the salted SHA1 hash for the key has less entropy than the key ...
4
votes
1answer
492 views

Securing a simple webservice against brute-force with mod-security

I want to provide basic defense against brute-force attacks against a simple HTTPS web service. The web service provides a login method (let's say at http://example.org/login) which gets passed a ...
1
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2answers
381 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 ...
9
votes
4answers
479 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 / ...
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4answers
622 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 ...
4
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4answers
502 views

Insecure to require numbers in passwords?

Earlier, I went to a site that required a number and special character, and it got me thinking – wouldn't that make the password easier to brute force? If you assume most passwords have around 12 ...
4
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4answers
2k views

Finding all links under a website

How can i find all directories and links under a website? Note that there is no link from home page to all other pages. For example if i have a domain like this users.company.com and each user will ...