Questions tagged [brute-force]

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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5answers
30k views

Someone is trying to brute-force(?) my private mail server… very… slowly… and with changing IPs

This has been going on for about 1-2 days now: heinzi@guybrush:~$ less /var/log/mail.log | grep '^Nov 27 .* postfix/submission.* warning' [...] Nov 27 03:36:16 guybrush postfix/submission/smtpd[7523]:...
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4answers
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Brute force prevention: where and when?

I design a 'secure' login system. Let's focus in the brute force prevention. In my Android client I have a counter that counts the number of times that the user tries to login, with false credentials. ...
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1answer
196 views

What are the best algorithms against known plaintext attack?

I'd like to encrypt files and their metadata as well. They will be stored in some sort of database (not yet decided, probably pgsql). The metadata can be for example the creation time, the ...
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1answer
2k views

John the Ripper Character Lists

How is it possible to use or prioritize umlauted characters - ä ö ü ß Ä Ö Ü - whilst brute forcing. I'm not using any wordlist, only dozens of CPU threads via the following command : ./john --fork=...
3
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2answers
333 views

Quantum Computer Advantage in SSH Login

I understand that quantum computers are many orders of magnitude faster than today's binary computer and that this is expected to enable decryption that was unlikely (it would take too long) with ...
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3answers
573 views

How secure is a password made up of three or four three-letter words?

According to this, a password such as dinwryran is secure against a brute-force attack. Is this true? If not, why?
5
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1answer
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How to interpret this statement against 4096-bit RSA

While I'd agree that double-sized RSA keys may pose more problems than the gain in security possibly justifies, I am having problems understanding the argument made here: https://gnupg.org/faq/gnupg-...
2
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1answer
375 views

Are there bruteforce programs that use letters of other languages? Arabic? Greek?

I came across a site that had the password strength meter. I tried using 'password' and the meter did not like my password. Then I happened to try 'password' but I used the arabic translation for 'a' ...
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1answer
609 views

How do I find out how long a password is for a 7zip aes 256 encryption? [closed]

I lost password to a 7zip, nothing important in it. But i'll still like to access it. I heard there is a way to find out how long the password is, but I dont know how.
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1answer
155 views

Can SSL traffic encrypted with a weak cypher be bruteforced?

Take the following scenario: Attacker performs a man-in-the-middle attack on Client, redirecting the DNS records of www.example.com to point to a malicious server Client connects to the malicious ...
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2answers
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bcrypt cost 10/12/14 brute force time?

Earlier I added bcrypt with cost 12 (15 is a bit too long for login, 12 looks about right). I'm also planning to add the https://howsecureismypassword.net/ open source version but I'd rather not ...
3
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1answer
71 views

To what extent should we defend against leaked credentials being tested against our system?

We see these kinds of attempts with some frequency. Normally a leak has happened from some other 3rd party, and an attacker has a big list of known account + password combinations that they can try ...
1
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1answer
976 views

cyberattack by password guessing admin account logon type 3

We have a 2008 R2 virtual server that is only used for logon via rdp or from local console. No VPN traffic is required. The server was under attack for a couple of days, viruses where installed etc. ...
2
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0answers
236 views

How easily could a picture password be hacked with brute force? [duplicate]

In Windows 8.1 Microsoft introduced a method to login using gestures over a picture. The picture password is determined by size, position and direction of any combination of circles, straight lines ...
3
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1answer
2k views

How to brute force a login page of an IP camera created in .asp?

I am new to stackexchange. I desperately need some help. I am doing my thesis on 'IoT Threats', one of my objectives is to try to brute force into an IP camera. I am using Kali Linux Hydra to do the ...
3
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0answers
717 views

Are enterprises Office 365 accounts overly exposed to brute force attacks?

Earlier this year the Scottish parliament was attacked by what described as a “Brute Force” cyber-attack. It was said that the attack targeted “MSPs and staff with parliamentary email addresses”. ...
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1answer
2k views

Why brute-force the password instead of the key directly?

This answer on another question on security stackexchange by a very reputed user explains why he prefers GnuPG over OpenSSL for file encryption. From what I understand, it can be summarized as this: ...
0
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1answer
334 views

Some questions about protecting recovery seed for Trezor/Nano S

If someone stole recovery seed (24 words) but you would protect it with additional passphrase, is it likely they could brute force your passphrase? How many guesses can there be made per second? ...
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1answer
182 views

Is signing safe from brute force attacks?

I am using itsdangerous to sign a string using a secret key. It says that the signing mechanism is HMAC and SHA1 and that it is an implementation of the Django signing module. Assuming I use one ...
0
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1answer
402 views

WordPress 4.7.2 Authentication Cookie Brute-force

I recently came across a WordPress (v 4.7.2) site with an exposed wp-config.php file, within which plain text server authorisation key secrets were accessible. Having read Mike Czumak's article on ...
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1answer
2k views

What makes brute force attack faster? [closed]

My question was, What makes brute force attack faster? Is it a bigger RAM, larger storage or a faster processor... because I saw a video of a man who put 7 GTX 1080's in parallel and it hacked a lot ...
3
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2answers
3k views

Should I use rainbow tables or bruteforce (NTLM)?

As part of security testing, I will receive around 150 to 200 Active Directory password hashes from Windows Server 2012 R2 (using NTLM?). I have found NTLM rainbow tables (1,5 TB total), that covers ...
3
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1answer
186 views

Brute forcing an OnePlus 5

I've never done a brute force before and I wanted to try it out on my phone. Considering there are 0-9 digits and 4 spaces, that gives me 10^4 combinations. I wanted to know how I can connect my Mac ...
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0answers
105 views

Protect unauthenticated interface from guessing attacks

I am currently encountering a publically available interface; accessible at least via web form/webviews and some stateless protocol (presumably REST). In the past this form allowed you to view your ...
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2answers
459 views

Key(session token) authentication vs default login/pass authentication

I am building web application and have an idea to build custom authentication system, which would be quick and secure. I do not want to use almost "default" login (email) / password combination. I ...
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3answers
2k views

What is a quantum computing attack?

As far as i know, a quantum attack is a brute force attack performed by a quantum computer. source: wiki Is this very simple definition correct ? or the scope of a quantum computing attack is bigger....
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1answer
2k views

How many passwords per second can a typical computer check? [closed]

I wanna know how many passwords per second my computer can check this is for brute force attacks. I looked everywhere and on this website and the computer listed on here are nothing similar to the one ...
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2answers
2k views

How to brute-force a somewhat remembered aescrypt password?

I have a file I encrypted with AES via aescrypt about 5 years ago. I remember a lot of things about the password with several prefixes and suffixes. I have experience as a programmer but not with ...
0
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1answer
182 views

Decrypt data with known text

So I have an encrypted text file that I know contains the phrase "potatoes are awesome" Is there a way for me to decrypt the text based on me knowing that phrase and the encrypted data? (I also don't ...
0
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1answer
995 views

Defence for brute force attacks to ssh

At some point in the past I had a small (physical) webserver. From day 1 there were brute force attacks to ssh. I looked it up a bit and I set up iptables to block IPs that try to connect to ssh more ...
4
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1answer
1k views

How does a private OpenPGP key's passphrase add to its security?

I am a novice user of OpenPGP. I use GPGTools for OS X. I have several connected questions, but difficult to find direct answers on the Internet. When I create a key-pair, the password I enter is a ...
3
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2answers
3k views

Placing IP address in JSON web token or session cookie

I'm relatively new to security and I'm looking to prevent brute force logins on a web application I'm creating. After doing some research, I decided to go with requiring a captcha after a user ...
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3answers
729 views

Can X.509 Authentication be subject to brute force attacks?

I am working on an application (using Spring Security) that has two possible user authentication mechanisms: either X.509 certificate (using mutual SSL handshake) or user + password For user+...
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1answer
804 views

Directory Traversal or File System Permissions? [closed]

A network administrator discovers several unknown files in the root directory of his Linux FTP server. One of the files is a tarball, two are shell script files, and last one is a binary- file is ...
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4answers
512 views

Understanding how to prevent rapid-fire login attempts

I'm having problems to fully understand how to prevent rapid-fire login attempts. My questions basically come from the The definitive guide to form-based website authentication. The final ...
8
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1answer
12k views

Bruteforce with hashcat, how to set the mask properly?

Let's say I've an hash of this type: test::::4e45c7bab093d7011e9b3a5df7d9fa88212beac5ac9c8c47:d6ff3373aa353f3b:123456 I would like to bruteforce it using hashcat, but I'm failing to set the correct ...
2
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0answers
367 views

Why Aren't CA Private Keys Vulnerable to Brute Force Hacking [duplicate]

I have read a bit about encryption up to this point and understand that server certificates are validated by having a Certificate Authority validate that certificate contents match the digital ...
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2answers
3k views

Is it possible to bruteforce a cvv code?

If I'm not wrong, the cvv code almost always follows a certain pattern based on the credit card number and dates. What are the possibilities to go through to hypothetically bruteforce a cvv code? Is ...
0
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0answers
112 views

Hydra returning error: “module option must start with http”

I am trying to brute force a web login password using hydra with the below command: hydra -s 8123 -x 2:8:aA1 -t 16 -m http://192.168.1.193 http-proxy I get [ERROR] module option must start with ...
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1answer
770 views

John the Ripper and incremental mode

I have a question about John the Ripper and it's incremental mode. As far as I know, the incremental mode is a brute-force mode, and it tries to get the password by systematic combining all ...
9
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1answer
556 views

How to get and use constantly changing cookie JSESSIONID values in Hydra?

Related: how to get cookies from aspx site to use it with hydra My problem is similar to the above case, I get "20 valid passwords found" but the server I'm trying to brute force sends the header set-...
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1answer
1k views

brute force ssh account with key-pair authentication?

Recently one of my servers has been hacked and it seems they got SSH access (logs are removed, ransom readme files created etc..). The account has a ssh certificate authentication (incl. passphrase ...
0
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1answer
529 views

Kali Linux Hydra question

Recently a friend of mine coded a website and he asked me to brute force it to test it HTML code of the page trying to use hydra on https://pastebin.com/D2iQXrNb (use Pastebin because I don't know ...
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0answers
95 views

No fields captured in BurpSuite

I am using burpsuite to bruteforce my routers login form, but I have encountered an issue... When I enter something into the password field, BurpSuite shows the request, but not what was entered. For ...
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3answers
1k views

Can I slow down a brute force attack by encoding password input data?

I'm building a php login form with only a username & password as $_POST data. But before submitting the form, a JS function check() will base64_encode the password input, then finally submits the ...
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2answers
2k views

Preventing a Brute Force Attack on API via limiter

I have an API that users can log into. I don't want it to be hacked. What if I limit each user to 60 requests a minute? Won't this significantly slow hackers down in a brute force situation?
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0answers
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Brute Force with Hydra Ignore timeout and 4 billion limit

We are doing an assignment where we are hacking eachothers websites or servers in school. I know the default username and know the default password is 32 characters long to ssh in. While I know I ...
9
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3answers
461 views

How to calculate brute forcing times/feasibility for remote attacks to include parallelism?

This is purely a thought exercise. Assume a server which does not implement throttling or lock on failed attempts. The server accepts a username/password request & sends back a Yes/No response. ...
3
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2answers
570 views

Should I publish IP addresses that try to brute force my private web server?

Ethically and legally, am I allowed to publish IP addresses that tried to brute force my LAMP server? It's a personal website/blog that gets brute forced a lot and I would like to publish them to my ...
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3answers
1k views

How to stop brute force attack that is DDoSing our server?

We have a web application and that's been frequently hit with random username and password to find a successful login attempt. We introduced CAPTCHA, random token generation but that didn't stop the ...