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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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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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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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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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 ...
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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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How to brute force a Java Applet in browser?

I am solving a CTF challenge and it is multi-layered: https://net-force.nl/challenge/level314/ (Modern browsers don't support Java Applets anymore and I had to download Opera browser 9.x to run the ...
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how to get cookies from aspx site to use it with hydra

I've been playing around with Hydra and .aspx site and I've hit a bit of a snag - Hydra responds letting me know that the first 16 passwords in my password list are correct when none of them are. ...
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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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Scan all possible files on server (Brute force Filenames)

I'm looking for a tool which can scan all possible filename combinations on a server and tells you what filenames the server responded to. So it would try something like: example.com/a, example.com/b,...
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It's really that insecure to have POP3 enabled in my gmail account?

Several people are claiming that you should turn off pop3 in gmail because it allowed bruteforce attacks on the password. Doesn't Google prevent this kind of attacks? What is the truth on this claims?...
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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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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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How to safely create a “honeypot (linux) user”

Would following be a feasible security feature to detect attempts? Creating a user with following specs: Username admin Password fairly insecure (not 123456, but a dictonary word) Special ...
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How to crack 10 digits with prefix password in John the Ripper?

I want to crack a password which pattern was 10 digits start with 0910 or 0912. So possible passwords would be e.g. 0910333444, 0910444566, 0912111222, 0912145632. How to configure the incremental ...
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Brute Force RDP Attacks Despite Having RDP Restricted to 1 IP - HOW?

I restricted the Firewall incoming rules for RDP under Scope to 1 Remote IP address (Local IP Address section is empty). This was done for both Public & Private/Domain Rules. This action ...
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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 airodump-ng). I'm ...
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Bruteforcing an iOS PIN

The iOS Security document describes several security mechanisms implemented in iOS 9. I am specifically interested in the actual security of a 4 digits PIN on iOS. I am looking for tangible ...
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Securing anonymous accessible URL with a GUID segment?

In my problem there is an existing system that works as a alerting or clipping service that runs user defined searches and generates results lists. These are setup by authenticated users and this ...
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Can passwords be brute-forced through RDP?

We had a small discussion about a security-related article at work today, and I was a bit surprised about one thing - they claim that some attackers managed to brute-force guess the password of ...
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Wireshark HTTP continuations (Hydra HTTP version)

I am trying to use Hydra to brute force a HTTP POST form page, however the page is returning a HTTP Continuation I'm not sure what that is. This is being caused by the HTTP/1.0 at the top of the ...
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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 ...
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Reasonable (BruteForce) Attempts/Second Estimate?

I've read various articles on password strength and passwords vs pass phrases (including the one from XKCD and its thread here), but most of those articles seem to be focused on online passwords, and ...
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How rf remotes for “cloning” rolling code find matching codes?

I've been tinkering with a rf (garage door) remote control that has a scanner mode (google JMA SR-48 for details). This mode works for Mutancode and Erreka which I assume would be similar to KeeLoq. ...
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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 ...
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what is the fastest and cheapest way to crack this kind of hash - md5(md5($password) + salt))?

I'm looking for a program that can use any GPU (ATI\NVIDIA) and can brute force a vBulletin hash - md5(md5($password) + salt)). I have the salt and hash. the password contains the symbols - a-zA-z0-...
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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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Remove Password Protection from XLS Document

Similar to what is listed here, http://datapigtechnologies.com/blog/index.php/hack-into-a-protected-excel-2007-or-2010-workbook/, is there a way to remove the password from an XLS (Excel 2003) ...
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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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What utilities exist to brute force a username and password?

I'm trying to persuade management to purchase two factor authentication for securing VPN and terminal server access. I've made significant progress by demoing TSGrinder, but would like to list other ...
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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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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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Does using characters specific to language make password stronger

So let's start of example. I live in England, and have a Polish keyboard. I can use Polish specific letters like ąćęłńóśżź, one could also use German ßäë etc. Would using those letters make password ...
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Do any routers report a brute force attempt?

In our work office, we have a router but the password for it has been lost. We don't want to do a factory reset except as a last resort. I could try brute forcing the login, but I'm afraid that some ...
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What scenario are 'extra' strong passwords and hashing algorithms actually protecting against?

Note: I completely understand the need for strong passwords & I understand that there is an issue of speed with hashing. I am just interested in better understanding the actual negative impact of ...
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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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Can a Windows or Linux password be brute-forced on a public network?

I am at a hotel that has a public network. I have a Windows machine with a wired connection to it. "Network and Sharing" has network discovery on. No folders are shared except "Users", which is shared ...
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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 ...
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Is passwords with combination of different encodings super safe?

I was thinking about generating passwords with combination of English, Arabic, Chinese charac. Is this pass secure enough against brute force attacks?
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Are there any known collisions of a “long” (64 bit) OpenPGP key ID?

We know that the "short" 32 bit OpenPGP key IDs can be easily brute-forced and the recommendation is to use the "long" 64 bit IDs or full 160 bit SHA1 fingerprint. However I am concerned that the "...
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Is using a phrase from a book as a password such a bad idea

I've been told/seen online that choosing a sentence or a phrase from a book and using it as a password is a bad idea. How is this true? Unless the potential attacker knew which book you used I don't ...
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Is logging into SSH with a 2048 bit SSH password less secure than logging in with a a 2048 bit private key? [duplicate]

I'm certainly not saying this is a "good idea," and I always disable password authentication on SSH servers. However, the question came up when talking to a friend: If your password is as long and ...
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Naive key stretching vs PBKDF2

What are the drawbacks of using a trivially simple key stretching approach such as the below Python example, compared to something like PBKDF2? The purpose is to harden an AES-encrypted file against ...
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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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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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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 ...
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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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Brute force algorithm to break symmetric key. How to find the program when current key is the correct one?

In a brute force program, sequential keys are tested against the public key in order to find the correspondent private key. My question is, how is the test done with each key that let you conclude ...
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Is TCP Sequence Bruteforcing dangerous nowadays?

I was reading about TCP sequence prediction which is described as almost impossible on all updated Operating System nowadays. The total amount of possible sequence numbers is 2^32-1 which, if we try ...
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Find salt from md5 hash if password is known

I have a salted MD5 hash and I also know the password. How can I recover the salt using tools like John The Ripper (I have JTR jumbo installed)?
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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 ...