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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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6answers
9k views

What would be the key size for a picture used as a key?

I'm working on a cryptosystem that uses colour pictures as keys for encryption. I'm trying to guess what is the key size of my cryptosystem in order to find the feasibility of a brute force attack. My ...
1
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1answer
266 views

What are the disadvantages of using Shamir's Secret Sharing to implement a Partial Password scheme?

Suppose I want to implement a partial password scheme, where the user authenticates by using two passwords: one a normal password, the other is partial, where he only needs to type the selected three ...
0
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0answers
275 views

How to mask attack a sha256 hash with following information using hashcat?

I am hashcat newbie and I want to crack a hash :) The answer is 1-15 (unknown) characters and it may contain 'a-z' 'A-Z' '0-9' and '_' . (A Twitter username) How may I mask attack a hash with above ...
0
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1answer
147 views

NMAP NSE script stopping after 900 seconds (15 minutes)

I am experimenting with ssh bruteforce over my home network using the ssh-brute nse script. I have a short list of usernames (just 12) but a long list of passwords (1M). I can't seem to get the ssh-...
1
vote
1answer
191 views

Manage Logs of Excessive Member and Server Authentication Failures

Currently, in our SIEM environment, we are attempting to reduce noise and any non-actionable items. One of the most frequent items we receive on a weekly basis is a report based on excessive member ...
38
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8answers
14k views

Is brute force a probable threat even if you enable CAPTCHA and rate limit logins?

Let's assume CAPTCHA is enabled with account lock out control (after five continuous failed attempts, the account will be locked for 15 min) on a system. Is brute force still a probable threat?
0
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1answer
1k views

Brute-Forcing DVWA login page with hydra

I'm learning how to brute force web login pages with a popular brute force tool called "Hydra". I'm using Kali Linux (VirtualBox) to do this. I've installed DVWA (Damn Vulnerable Web Application) and ...
1
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1answer
611 views

Are partial passwords a security improvement over full passwords?

With full password authentication, you need to enter the full password every time. With partial password authentication, you're asked for some subset of the password each time, and which characters ...
1
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1answer
79 views

Why are SQL servers not attacked as frequently as ssh servers?

I have a server running with both SSH and MySQL accessible to the public internet. Both run on default ports (22 and 3306). The ssh server is attacked by bots all the time. This is the output of ...
1
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1answer
120 views

Lost password for encrypted external HD

Have an old filevault encrypted external hard drive. Would like to access but have forgotten the password. However I do remember the style of password (XKCD four word style) and remember two of the ...
2
votes
1answer
115 views

Slow Hashing Without a Salt?

I'm trying to design a security scheme that involves a shared secret but isn't a traditional account password situation. The server would store a set of "keys", each of which has a blob of data ...
1
vote
1answer
365 views

Please explain the vulnerability for the pre-shared Key for IKEv1 brute force IPSec

After the vulnerability was released for IPSec IKEv1 PSKs, our organization decided to increase the size and complexity of the PSK. However, upon releasing the new PSK we had a few issues: ...
0
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1answer
99 views

How is my employer accessing my router when employer's laptop is wirelessly connected to my home network

I have a modem bridged to a modern router running open source software and heavily secured. I have all connections to the router through a personal vpn from a dedicated provider. During work from home ...
1
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1answer
614 views

hashcat specific brute force

Is this scenario possible: I know the first three letters of the password (exact), i know the password is between 10-14 characters, i know the rest of the characters are "b,t,p,1,3,6,7" which can be ...
1
vote
1answer
3k views

Best tool to BruteForcing RDP

I have tried many tools and to do not seem to be successful with locking out an account I am testing on my network with an RDP domain. I used crowbar, ncrack and THC hydra but they don't seem to be ...
0
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2answers
243 views

Protect MySQL against brute-force attacks on dedicated CentOS 7 server

I have a database in a dedicated server (CentOS 7) setup by an external provider. I see a disgusting amount of brute-force attempts in MySQL log file every day. I know the best option would be to not ...
0
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1answer
139 views

Are there any good brute force programs in C#? [closed]

I'm planning to research & learn from brute force methods, but all the popular ones I found like John the Ripper or hashcat are written in C & OpenGL which I don't have much knowledge about so ...
0
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1answer
2k views

THC Hydra on Windows RDP Domain

I am testing a bruteforce on a windows rdp server within a domain. It seems to not be working because nothing is locking out the account I am targeting. How do you specify a domain username? I tried ...
2
votes
2answers
489 views

Breaking .kdb (KeePass 1.x) file

During a penetration testing lab, I have obtained access to a .kdb file of a KeePass 1.25 (password management). Therefore I tried to find a way to obtain the file key file or key and after ...
2
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0answers
363 views

Brute force hex password with exactly two special characters using JohnTheRipper

I want to optimize the way I'm using John the Ripper. I have a password with a know length (9) that consists only of (lower-case) hex characters and exactly two special characters. First I tried ...
0
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2answers
74 views

Cryptography as an ecosystem

I was thinking about a thought experiment. Let's imagine a world full of crackers such that whenever you encrypt something there will be someone who will try to crack your cryptographic key through ...
1
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1answer
112 views

Online brute force attack which will continue in background [closed]

I don't have enough bandwidth for brute force dictionary attacks so I'm searching for a website or a way that I can do brute force attacks as a background process even if I turn my internet ...
0
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1answer
444 views

Is this possible to brute force 25 billions billions password in less than a month?

i'm using Hashcat for a while & try to solve this challenge: is this possible to crack at least half the possibilities combinations password of 10 character using 94 characters from keyboard with ...
2
votes
2answers
202 views

is there an upper limit on time to brute-force a password, based on acceptable login delay and hardware speed ratios?

Suppose a user uses a password to log in to their PC. When the user logs in, the PC applies a cryptographic function to the password and compares the ciphertext to the stored ciphertext of the known ...
0
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3answers
292 views

Brute forcing - How difficult?

I'm doing a research project and I have a question regarding how difficult it would be to brute force something. Say there is a piece of text - "My name is James" Removing the whitespaces yields "...
1
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1answer
343 views

Is it possible to specify multiple values for failure condition (F=) using Hydra?

I want to brute-force a site using Hydra (https-post-form) that I don't know valid login credentials for, so I cannot specify a value for success condition (S=). Failed logins result in a redirect ...
1
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2answers
161 views

Is something like fail2ban necessary for a rate-limited key-only (no password) ssh login?

As far as I understand, bruteforcing ssh is only attempted for passwords, not keys (barring edge cases where presumably the NSA wants to break in). So if a server has disabled (in addition to root ...
0
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1answer
532 views

How to configure hashcat to only hash fixed length passwords with N digits?

I know of mask and dictionary attacks. Using a mask attack, I specify the charset for each position in the password pattern, e.g., ?1?1?d?1?d?1?1?d, where ?1 := ?l?u?s. But how do I tell hashcat to ...
0
votes
1answer
682 views

Which hashcat hash mode is closest to that used by BitLocker?

I'm trying to get a hypothetical benchmark for the BitLocker hash mode if Hashcat would support it. Which (-m) mode is closest to BitLocker's latest/default algorithm? From Google searches I learned ...
1
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0answers
268 views

How to recover forgotten AES-256 password with bruce force?

The password was set on a flash drive using LaCie Private-Public for Windows 10. The password is 12 character long. For each character, I know if it is a number, special character, lower case letter ...
92
votes
8answers
16k views

Can secret GET requests be brute forced? [duplicate]

Say, I have on my server a page or folder which I want to be secret. example.com/fdsafdsafdsfdsfdsafdrewrew.html or example.com/fdsafdsafdsfdsfdsafdrewrewaa34532543432/admin/index.html If the ...
0
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1answer
622 views

Avoid brute force attacks on oAuth authorization server

I've been looking into the oAuth 2 authorization framework for a while now. Yesterday I started wondering how to prevent a brute force attack during the Authorization Code Grant flow (https://tools....
5
votes
3answers
3k views

How to protect our server from brute force attack? [closed]

One of the most common cyber attack is Bruteforce , what are the mechanisms available to protect this attack and how industry apply these mechanisms to mitigate the attacks (best practices)?
3
votes
1answer
110 views

“Targeted” Brute-Force an Local App password

I can't remember my password for a locally installed app but I wrote it down poorly and am sure of 6 letters/numbers out of 11. I generated a list of all the possibilities given that the badly ...
7
votes
1answer
429 views

Brute forcing encryption password (self destruct after 4 attempts)

My colleague at work lost the password to his external hard drive (HDD not SSD), a WD Elements. He remembers that his password was simple and 8 characters maximum. The problem is the encryption ...
4
votes
1answer
344 views

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 ...
-1
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1answer
745 views

Can brute force or dictionary attacks be detected when using the WiFi protocol?

Can the WiFi protocol recognize when a brute force or dictionary attack on it is occurring? WiFi gives the user an authentication failed message after entering an incorrect WiFi password several times....
-4
votes
1answer
461 views

How can WPscan bruteforce passwords without hitting any limit rate?

I've just watched this video which shows the attacker bruteforcing both usernames and passwords. How can this be achieved without hitting any limit rate? Does it mean that WordPress doesn't provide ...
2
votes
1answer
1k views

Maximum tries for 2FA code?

I am building a website and I am implementing two factor authentication (2FA). The second factor will be a random 6 digit code like those from Authy. This site will store very confidential information....
2
votes
1answer
485 views

Tools and computer specs for password cracking [closed]

To polish my penetration testing skills I want to attempt to crack NTLM/NTLMv2 hashes (via dictionary/wordlist attack) extracted from Active Directory / SAM database, where the underlying passwords ...
5
votes
2answers
477 views

Is there a way to see what is program is causing RDP attempts on computer

One of our servers (running RdpGuard) shows multiple failed attempts from specific users' machines (3 to be exact) and I can't figure out what is causing them. One user is local and two are remote ...
2
votes
1answer
1k views

How is it that tools like Hashcat, JTR able to bruteforce an NTLMv2 hashes?

With regards to the following question about the feasibility of (brute|dictionary|rainbowtable)-forcing an NTLMv2 hash: How feasible is it for an attacker to brute-force an NTLMv2 response captured ...
0
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1answer
142 views

Database logs have multiple “Logon Login failed for user” from different IPs

Background: I have an SQL Server database running on Amazon RDS The AWS dashboard has a section for logs and whenever I check the logs I see the following: 2018-04-27 06:10:26.00 Logon Error: 18456,...
2
votes
1answer
269 views

Hydra - all passwords work

I want to test some mechanisms of my website when the password of a single user is entered a lot of times in a short time incorrectly in the login form. Therefore I got Hydra (for windows) on GitHub. ...
7
votes
2answers
11k views

How long would it take to brute force an 11 character single-case alphanumeric password?

My previous home wifi router's WPA2 password was permanently fixed to FZ4HBCKHGC8. How long would it take to crack via brute force? Or more pragmatically: How long would it take to exhaust all ...
5
votes
2answers
525 views

Avoid being hacked with brute-force attack

During the last week, our company website has been under a weird brute-force, this attack actually led to hacking an admin account. Our website is a wordpress site. The attacker keeps performing POST ...
0
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2answers
3k views

Hydra fails with “[ERROR] target ssh://192.168.16.128:22/ does not support password authentication.”?

I've updated Kali 2.0 to newest version - it is installed using VMWare. Now, every time I use hydra to brute-force SSH, I get the following error: [ERROR] target ssh://192.168.16.128:22/ does not ...
0
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1answer
1k views

How can hackers get 1 billion passwords per second?

So I'm interested in Brute Force attacks and I have made them with Python 3 and C++. However, those only reached a max of about 20 million passwords per second. I know for a fact that 1 billion ...
1
vote
0answers
145 views

Using hydra on a website that has the same response for both a wrong and correct password

I got my hands on an old-ish residential gateway with SIP support and two analog phone connections. I want to use it for it's SIP support to use analog phones with my SIP provider. I didn't know the ...
0
votes
1answer
156 views

Should a CDN service like Cloudflare protect against Brute Force Attacks, or only from DDoS?

I know that CDN services usually protect a user by hiding it's original machine's IP and by screening (and banning) any attackers that send too many requests in the form of DDoS. But should a CDN ...