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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2
votes
3answers
247 views

How can hackers guess passwords (using dictionary attack or brute force) without being locked out?

Nowadays almost every website you want to register in; is asking you to create a complicated password...But why cant we use simple passwords? I am just wondering because in case of multiple wrong ...
8
votes
4answers
696 views

Can anti-CSRF token prevent bruteforce attack?

I am not much experienced with brute force attacks but I was wondering Suppose, you have a website www.example.com and you want to do brute force attack on that login form but that login form is ...
0
votes
3answers
117 views

What are the differences between dictionary attack and brute force attack?

Can someone explain the major differences between a Brute force attack and a Dictionary attack. Does the term rainbow table has any relation with these?
-1
votes
1answer
34 views

How to prevent ddos and brute-force attack by restricting IP's on Wordpress website

I want to make wp-login.php and/or wp-admin accessible only from one country. If I want wp-login.php access only from USA then my approach from .htaccess is like below <Files wp-login.php> ...
0
votes
1answer
103 views

THC Hydra 16 Valid Passwords? [duplicate]

So when i do hydra -l Admin -P "rockyou.txt" -s 80 192.168.13.1 http-get / it doesnt work for me, it says all 16 passwords are valid, but none of them works, can anyone help me with this? I tried ...
16
votes
6answers
2k views

Is there a brute-force attack similar to what they demonstrate in movies [duplicate]

Since I was a teenager (that's 20 years ago) and till now-days you see movies with professionals stealing a super-computer and use it to crack a password or a home security system using brute-force (I ...
0
votes
1answer
52 views

Why is the brute force search time for hashing algorithms 2^(num_bits / 2)?

I noticed that the brute force times (the time it takes to find a message that hashes to a given hash) of various hashing algorithms seems to be 2^(num_bits / 2). For example, people say that brute ...
4
votes
6answers
3k 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
votes
1answer
101 views

Is there a benefit to encrypting a file multiple times? [duplicate]

If I had to store a text file with some confidential information on the cloud, would encrypting the file multiple times (say, 3) with different passwords using WinRAR (AES with a 256 bit key) provide ...
-1
votes
1answer
47 views

Where can I find good word list for MySQL 5? [closed]

I wonder where can I find good collections of dictionaries which can be used for MySQL 5 dictionary attack? I just need MySQL 5 word lists / dictionaries. I found a lot of MD5, SHA1, etc. but not ...
-3
votes
2answers
87 views

Time it takes to crack a password on site like yahoo [closed]

I have a question. If you were using a password brute force/dictionary attack utility on a site like yahoo or another site, how long would it take to crack a password like Jah13Wootiang if Wootiang is ...
2
votes
1answer
78 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 ...
2
votes
1answer
89 views

Why do so many cracking attempts originate from China?

I recently put a Linux server online and it didn't take long until I had the first attempts to brute-force the SSH login. It's not that I am worried about that - I trust the security of my server. But ...
6
votes
4answers
16k 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 ...
4
votes
3answers
128 views

Wordpress Brute Force Attacker knows real admin Username -

I've noticed a brute force attempt on several different Wordpress installs that know the right admin user name for those respective sites... It seems very strange that the hacker would be able to ...
-4
votes
7answers
737 views

Are passwords made up from concatenating a few foreign words better than shorter random characters? [duplicate]

Does it make sense to insert a foreign word into a paraphrase to mitigate against brute force? For example: "pussiMeansCatInEskimo" "caballoMeansHorse" "CatIsGatto" "SalopeMeansBitch" ...
1
vote
2answers
142 views

Brute force alphanumeric password using JohnTheRipper

I recently recovered a zip archive with some files I need access to, but I can't remember the password. All I can remember is that the password was short (around 3-4 characters), and contained only ...
1
vote
2answers
83 views

do ISPs implement security measures?

For example, if a user is receiving a denial of service attack, with huge amounts of packets being sent to him to disrupt his service, will the ISP notice and stop the offending traffic? Another ...
-1
votes
4answers
64 views

Confidentiality of file hashes

Context: I have a directory full of sensitive company files. I want to compare these files with a colleague at a remote location, without the need for a secure connection. Is it safe for me to ...
0
votes
3answers
94 views

Safety of Password Hashing Using bcrypt Done on Client Side

I am currently using a technique where I send the username/password in cleartext (using https) to the server, which then does bcrypt and compares to the db. Standard practice. It is considered safe. ...
1
vote
0answers
52 views

Bruteforce using crunch and Aircrack (custom starting number?)

I'm trying to do a Bruteforce attack on a handshake taken from my wireless network that is not WPS enabled. The reason I'm doing it is because I'm testing how strong a 10 digit phone number is as a ...
0
votes
3answers
102 views

User Account Guessing [duplicate]

I'm doing some research on user account guessing, and wanted to ask a question about some "bad practices". My thought is generally this is a trade-off between great user functionality/UX and ...
-1
votes
1answer
130 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
153 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
4answers
426 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 ...
0
votes
2answers
77 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 ...
8
votes
1answer
338 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 ...
1
vote
1answer
435 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
2answers
185 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
224 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
214 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
68 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: ...
2
votes
2answers
6k 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. ...
0
votes
1answer
530 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
98 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 ...
-2
votes
4answers
9k views

Brute-force an SSH-login that has only a 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 ...
1
vote
1answer
385 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 ...
12
votes
1answer
306 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 ...
3
votes
4answers
233 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
124 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: ...
18
votes
2answers
10k 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 ...
1
vote
2answers
616 views

Can you crack a Mailinator “Alternate Inbox Name?”

From their FAQ: What are "Alternate Inbox Names" ? There are 2 ways to get email into any given inbox. When you check an inbox, listed at the top is the Alternate Inbox name. Emailing that alternate ...
0
votes
1answer
57 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
152 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 ...
2
votes
1answer
437 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: ...
3
votes
4answers
449 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 ...
12
votes
4answers
507 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 ...
55
votes
8answers
88k 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 ...
0
votes
0answers
191 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 ...