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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Implementing brute force attacks on hash values in Javascript

I'm working for my bachelor thesis at the end of which I aim to implement a proof-of-concept Javascript-based hash cracker. The idea is to work like this: Users can submit a hash value along with ...
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1answer
548 views

Academic papers on GPU password cracking?

Are there any scientific papers or publications on GPU password cracking?
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2answers
190 views

How to generate a password dictionary for a specific use

I have a locked work file that I need access to. Unfortunately, the company that provided the file is no longer in existence and I can't track anyone down to help me out. The file is encrypted and ...
3
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3answers
239 views

How is truncation according to PCI DSS secure?

In section 3.3 of the PCI standard, it says that when displaying PANs, limiting visibility to the first 6 and last 4 digits of the PAN is considered secure. Doing some quick math, on a 16 digit PAN, ...
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4answers
613 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 ...
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1answer
986 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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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 ...
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1answer
1k views

How resistant is the iPhone encryption against brute-force attacks?

I just read the following paragraph in an article from the New York Times about Apple encrypting iPhones by default): Breaking the code, according to an Apple technical guide, could take “more ...
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1answer
2k 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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2answers
1k 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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3answers
437 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 ...
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2answers
110 views

Calculating the time required to brute force a random code

Say we have amount random entry codes of length characters from an alphabet of size alphabet. The number of possible codes is then easily calculated as keyspace = alphabet ^ length. Now take an ...
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2answers
2k views

Closely spaced failed logins in auth.log

I have a raspberry-pi (running GNU/Linux) and I recently allowed my router to forward port 22 (ssh) to the raspberry-pi so that I could log in while away from home. I then noticed a bunch of ...
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4answers
2k 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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1answer
434 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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2answers
25k 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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2answers
112 views

Is there known statistics of passwords used during brute force password attacks?

I have been reading quite a bit about brute force attacks and I am wondering whether the passwords that are used in such attacks should be kept around so as to later prevent my users from having those ...
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1answer
471 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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0answers
25 views

Reaver stuck at flow_handler

I tried to run Reaver against my router at home using an Ubuntu 15.10 laptop. The command used was: sudo reaver -i mon0 -b XX:XX:XX:XX:XX:XX -vv -c 7 -a (the channel I got from aerodump-ng). I'm ...
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1answer
204 views

Writing your own John the Ripper module

I have a script in C, which is able to determine the password of certain data. It uses HMAC and RC4 algorithms to encrypt the given password and then compares that later to the given data. If they ...
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0answers
285 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
835 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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1answer
2k 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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1answer
683 views

Reporting an IP address

This morning while checking /var/log/secure to troubleshoot an issue with my Centos VPS, I found that there has been too many SSH bruteforce attempts from 54.93.174.60 for the past couple of days. I ...
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2answers
251 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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3answers
2k 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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1answer
115 views

Is a large encrypted file more secure than a small one?

Does encrypting a large file and subsequently having to decrypt a large file make it more secure than a small one when attempting to brute force it? If you have to brute force a 25GB file and a 250MB ...
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2answers
926 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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1answer
185 views

How much does knowing the zxcvbn password strength help an attacker?

On an answer to the question How critical is it to keep your password length secret?, Mike Ounsworth commented that by storing the zxcvbn-calculated entropy of a password you make it easier for an ...
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3answers
6k 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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3answers
148 views

Feasibility of time-based database brute-force attacks on websites

I recently learned that there is an attack that utilizes the fact that when brute-forcing a compared string (e.g. hash from a password or token) in a database the query fails a few nanoseconds earlier ...
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1answer
98 views

Long passwords and key derivation functions

Not being a security expert, I have a rather theoratical question that I have been thinking about for quite a while now: Let's imagine an encryption software that takes a user-provided password, ...
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1answer
561 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
268 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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3answers
90 views

Nmap http-brute - Supplying arguments for bruting via GET

I'm attempting to brute a site in my test lab with Nmap's http-brute nse, which has the URL structure https://192.168.101.6/api/auth?email=a@b.com&password=pass Unfortunately Nmap's official ...
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1answer
558 views

Is there any practical attack on port knocking method?

I was wondering, how can I bypass the port knocking method. Is there any public vulnerability or method for attacking port knocking services? For example: I know an SSH port is behind a port ...
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4answers
915 views

One-Time-Passwords resist against bruteforce attacks? Immune Alternative?

Does a One-Time-Password like Google Authenticator or YubiKey protect against brute force attacks with unlimited computer power? If not, what algorithems are immune to bruteforce attacks against ...
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1answer
2k 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
99 views

my bruteforce prevention has major downsides - any ideas?

I'm currently searching for the best way to prevent my software's webportal from bruteforce attacks and came up with the following idea: 3 login attempts without any visual challenge after 3 failed ...
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3answers
122 views

Does brute forcing require a password and username list?

I have been learning metasploit. One thing I noticed was that, all the videos on YouTube, which said "Brute forcing", used a password and a username list. My question is that, won't this be called a ...
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1answer
3k 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)?
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1answer
2k 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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1answer
846 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 ...
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2answers
240 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
851 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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2answers
67 views

Isn't ssh-copy-id exposing to a brute force attack?

It is a common knowledge, that using keys to authenticate ssh users is more secure than using passwords. However, even with password login disabled, when running ssh-copy-id I am still asked for ...
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2answers
169 views

How can I make wordlist smaller size?

I've been thinking if I create numeric 8chars wordlist and then compress it, can I directly input compressed wordlist into aircrack-ng or is there a way to make a smaller size wordlist, because if I ...
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1answer
213 views

P12 private key vs private key file : what is more secure?

The question is a bit tricky because they don't have the same purpose but : Do both kind of file face the same security issue concerning private key protection : password strenght ? (PBKDF2 as both ...
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2answers
382 views

Temporarily save failed logins password hashes for using against brute force attack

My question is about online brute force attacks, that try to authenticate in the website. 1) For the first case if the requests are coming from the same ip, I think this are relatively easy as after ...
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2answers
163 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: ...