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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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 ...
9
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2answers
6k views

Why limit passwords to ascii printable characters? [duplicate]

Possible Duplicate: Do non-keyboard characters make my password less susceptible to brute forcing? Every article on password security that I read tells people to make the password more ...
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5answers
68k 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 ...
9
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1answer
207 views

Long running SMTP session

I recently noticed an SMTP session on my server which started when a remote host connected but never seemed to result in any emails being delivered. I could see that it was probably a SPAM site and so ...
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7answers
955 views

How can I prevent users from using bad passwords in my web application?

There is a long discussion on whether it's the responsibility of the user or the system administrator to deal with the strength of the password. Obviously, the password is a very private thing, but ...
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5answers
41k 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. ...
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3answers
2k views

time to crack file-encryption password - more than just iteration

I have often seen that takes x amount of time to crack a certain length password. But this just seems to be the amount of time it takes to iterate through all the possibilities. What about the time it ...
8
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3answers
3k views

Can ssh keyfile security be broken in a few hours if the file is exposed?

At this link there is a claim that if an RSA key has a strong passphrase security might be broken in a few hours if an attacker has the private key. Is there something weak about the security of RSA ...
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3answers
7k views

Is .htaccess protection secure enough?

For the moment we protect a directory on our site with .htaccess and .htpasswd. But I was wondering how secure this is? Are there things I should watch for or can do make it more secure? I don't know ...
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4answers
7k 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
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1answer
1k views

Harden a server against mass SSH DoS attacks

How can a Linux server be protected against an attacker that tries to open a large number of SSH sessions (probably trying to brute force a password) that no ports remain to be able to legitimately ...
8
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1answer
561 views

Can/do botnets brute force “high value” users of services like Gmail?

On an intranet a login is generally disabled after a very small number of failed logins. But a public email service like Gmail can't do the same, otherwise pranksters would just be continuously ...
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3answers
3k views

Why is it harder to brute force an iphone than a zip-file?

Having only 1,000,000 possible combinations, an encrypted zip-file with a 6-digit numeric password, could be brute force cracked within a second. But for an iphone (let's say iOS9 if it matters), it ...
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5answers
1k views

Are there any security measures that are resistant to a brute force attack?

I'm not talking in particular about encryption, but security as a whole. Are there any security measures that can be put in place to protect data and/or a system that can withstand even a hypothetical ...
7
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3answers
962 views

It is possible that brute force attempts are successful before the worst case, correct?

When I read about a password being secure and stating that it would take X amount of week, years, etc. isn't that referring to the worst case? What happens if the brute force method is successul in ...
7
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3answers
1k views

Why do we have such big keys?

In Chapter 7 of Applied Cryptography, Bruce Schneier claims that, due to thermodynamic limitations, "brute-force attacks against 256-bit [symmetric] keys will be infeasible until computers are built ...
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4answers
2k 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 ...
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2answers
3k views

Dictionary Attack on Wifi

I know a few people with pretty weak passwords. What kind of systems exist to prevent dictionary attacks? Would it make sense to restrict the number of connection attempts in a certain timeframe? ...
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5answers
3k views

How unlikely is it that a Google Doc link is guessed?

Most (if not all) of us know that a Google Doc link looks something like this: https://docs.google.com/document/d/13P3p5bA3lslqEJT1BGeTL1L5ZrQq_fSov_56jT9vf0I/edit There are becoming several tools ...
7
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2answers
202 views

Realistically, how much added security does having a passphrase on a ssh key have?

Let's assume ssh key brute force is unrealistic. It seems to me your greatest vulnerability would be someone gaining access to a client filesystem. If that's the case then key loggers and a host of ...
7
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3answers
2k views

Can I spoof IP addresses when attempting to brute force a login?

I am testing my website with hydra brute-force software. But accessing my apache conf remote server file, it seems that an attacker can't log-in more a limited number of times per seconds. Does hydra ...
7
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1answer
1k views

Brute force login attempt from spoofed IP's

I see that many of my WordPress installs are being hit with 1000+ failed login attempts using non-existing 'admin' account name. The requests come from different IP's every time, and I see IP's such ...
7
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2answers
125 views

Is lack of wildcard DNS entry a security vulnerability?

A friend of a friend received an email from a security researcher that looks legit. Researcher submitted several vulnerabilities, one of the them reads like this Vulnerability # ... Title : ...
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2answers
664 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 ...
7
votes
1answer
15k views

Is my router vulnerable if WPS is enabled but WPS pin code is disabled?

I was reading about Reaver and wi-fi protected setups (WPS). In my Netgear router I have the option to disable the WPS pin code, but still have the WPS push button enabled. Am I secured with such ...
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4answers
2k views

Password entropy in layman's terms

Entropy is a term used often in relation to password security and brute-force attacks, but it is a topic that can get complicated quickly. What is the best way to describe password entropy (what it is ...
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5answers
2k views

Increased security with keepass

I am using keepass for securing passwords. I have a reasonable password, but if someone got hold of the file I am sure eventually they could brute force it. I was thinking of using a key file as ...
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3answers
340 views

How much added security do I really get with a longer key size?

Imagine I have a cipher which supports keys of 128, 192 or 256 bits. Suppose that there are no vulnerabilities in the cipher regardless of key length. I'm going to use it to encrypt something, and ...
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4answers
3k views

Are there lists of most common words or ngrams used in passwords and passphrases?

I've been thinking about ways to focus brute forcing dictionary attacks on passwords and passphrases based on the assumption that certain words, combinations of letters, and combinations of words are ...
6
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4answers
759 views

Can't brute force password cracking somehow be throttled?

Online articles mention the importance of a strong password and suggest that hacking tools allows bad guys to attempt millions of passwords per second. I am wondering why OSes and websites and such ...
6
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6answers
14k 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 ...
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3answers
1k views

Attack vectors for brute-forcing website passwords

When talking about password security, a lot of discussion centers on the risk of a password being guessed in a brute-force attack. For websites where a user has registered an account, what are the ...
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2answers
21k views

Is it possible to crack a PIN / PUK code on a phone SIM card?

When deploying a mobile phone best practices policy, one of the points which were raised was the requirement for the user to protect his SIM card with a PIN. The theory is that three failed attempts ...
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3answers
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NTLMv2 resistance to bruteforcing

I have a question regarding NTLMv2 resistance to password bruteforcing. I know that some modern graphic processors (like Radeon 6990) are able to calculate billions hashes per second and crack NTLM ...
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3answers
1k views

Is Twitter digits login (sms auth code) insecure?

Twitter released(some time ago) a new kit named Digits which allows the client to login with a phone number and an authorization code (received through sms). I find it great for the user experience ...
6
votes
1answer
8k views

What is the fail2ban default setting for SSH login attempts?

I tried to block myself from my own server to test if fail2ban works correctly, so I tried ssh login and used a wrong password over and over. But I was blocked only after 13 failed logins instead of ...
6
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2answers
1k views

Apple vs DOJ - how strong is the 10-try wipe brute force barrier?

Out of curiosity and with the hope of helping other beginners and journalists. The current Apple vs DOJ standoff in a nutshell - Apple is resisting DOJ with statements like what they're asking is ...
6
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2answers
293 views

Do I REALLY need to change my LastPass password?

Last weekend LastPass' network was compromised and that a list of email addresses along with the hashes of the master passwords were stolen. It is being recommended that LastPass users change their ...
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3answers
326 views

How do I secure my advertisement space against ad overlay browser attachments?

I don't really have an issue with advertisements simply being blocked by individual users who are visiting a customers site or my own site. As an individual you have the freedom to choose not to look ...
5
votes
4answers
26k 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 ...
5
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5answers
2k views

What password cracking software is commonly used?

I am curious to know how secure my passwords are. What password cracking software is commonly used? Preferably open source. EDIT: I am actually looking to crack my passwords used on services I ...
5
votes
8answers
680 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 ...
5
votes
4answers
214 views

software to keep a list of IP that try to access ssh over a set of rules and feasibility

i'm interested in software or set of scripts to keep a lists of filtered IP that attempt to brute-force ssh, and to label an IP as brute-forcing i would add some checks like: one attempt to log as ...
5
votes
4answers
5k views

Brute force vs other methods of recovering passwords from shadow file

Do you know any good approach for de-hashing/actually bruteforcing hashed passwords in the shadow file? On various operating systems, any good solutions/methods/programs. Or is it better to upload ...
5
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1answer
725 views

Perfectly Robust Hashing Scheme, or Completely Over-Engineered?

This is going to get long, so prepare. Basis of the question is, Do all these steps improve security, or am I completely overthinking the problem? Are my assumptions/thought process valid? We all ...
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4answers
5k views

Finding all links under a website

How can i find all directories and links under a website? Note that there is no link from home page to all other pages. For example if i have a domain like this users.company.com and each user will ...
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3answers
4k views

Avoiding Brute Force Attacks in a Web Based Login Form

My login form uses Ajax so it doesn't need to reload if the password is wrong. A PHP script process the request and creates the session if the credentials are right. My idea is to have the PHP script ...
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3answers
4k views

What are the odds of brute-forcing an archive with 256-bit encryption?

I have a file (a stand-alone archive). I lost the password to it, but it has been encrypted using 256-bit encryption. The password is some 20-odd characters long (including non-alphanumeric ...
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2answers
8k views

Can DES-based hashed password be recovered if salt is known?

Can a hashed password be recovered if the hashing is done with DES based crypt function in PHP and both the hash and salt are known by the attacker? Consider the following example: $salt = 'mysalt'; ...
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2answers
7k views

Faster methods for decrypting a TrueCrypt disk, esp. knowing the algorithms used

I encrypted (with TrueCrypt) all my hard drives and had the passwords stored in an encrypted file on my USB disk. The passwords are all (except one) 50 character randomly-generated ciphers, there's no ...