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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Web & insecure HTTP - Using RSA for encrypting passwords on the client side

I used client side password hashing in my register and login project. Its purpose is to prevent passive adversaries/eavesdroppers from discovering users' plaintext passwords when HTTP requests are in ...
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Throttling failed login attempts: exponential timeout? by IP? using a session cookie? captcha?

I'm beginning to think this is not as simple as it looks, and many "accepted" answers here and in SO have alternative answers that criticize them. Here is what I have gathered so far Most of what I ...
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Brute-force heuristics used in password cracking

Existing questions on this site discuss some of the heuristics used by password cracking tools to avoid doing a completely naive brute-force search (for example, "dictionary word with number ...
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Do SSD's offer significant performance boost for Scrypt?

Being a memory intensive hash, I was wondering if SSD's offer any appreciable performance boost for brute force attacks.
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How can Facebook possibly stop a bruteforce attack on an account?

I've been doing some research on hacking recently and I found some very interesting tutorials on brute force cracking. I have some questions to ask and I'll be using Facebook as an example. Let's say ...
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How long to brute-force WPA password?

Bob has a password (for his WPA encrypted wifi) which is 8 characters, all lowercase, and not a dictionary word. Eve lives next door to Bob and wants to illegally hack his WPA. The number of ...
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Automated URL Discovering

I built a simple server containing static files at /files/ and I'm attempting to discover them using automated tools. I'm using wfuzz to brute force on the URL but is that the only way? Is there any ...
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Is brute-forcing the only way to crack WPA?

I don't know much about how WPA algorithms work internally. Is brute-forcing an AP the only way to crack WPA? (or to get associated with AP) Another question is about Reaver-WPS, what if an access ...
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195 views

Could a password hash that's prone to more collisions provide better overall security?

Website security breaches seem to be a common occurrence, giving the attacker password hashes that he can conduct a brute force attack against, often given him a list of passwords that will work on ...
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792 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 ...
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mysql security logging

Is there any logging available that logs mysql connection attempts to the port, login attempts, and times succeeded with username, IP address and date time? Im trying to detect brute force attempts. ...
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How can I restrict users' connection attempts to my FTP server?

Is there any way possible to restrict user to make a connection to the FTP server on my Windows XP computer? I have an FTP server established in Windows XP and now I want to make access to that FTP ...
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Blocking Chinese IP addresses

I recently checked one of my servers' auth.log file and noticed some very suspicious activity. I recently shut down my server's ssh daemon, so the logs end on Jan 22, but what I noticed after ...
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Estimated cost to make a brute-force WPA2 attack feasible

It's been shown that a brute-force attack on WPA2-Personal is possible in a reasonable amount of time. These successful attacks appear to be limited, however, to researchers who have the budget to ...
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How resistant is the iPhone encryption against brute-force attacks?

I just read the following paragraph in an article from the New York Times about Apple encrypting iPhones by default): Breaking the code, according to an Apple technical guide, could take “more ...
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Can a Bitlocker To Go user pin be brute forced?

I have a external hard disk and protected a partition on it with Bitlocker To Go. I printed the recovery code but I lost it. I can't remember the user PIN either. If I could only know the first ...
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Are more passwords breached via dictionary/bf attacks or via packet-sniffers/key-loggers?

This question has always intrigued me whenever the subject of passwords is brought up. Does anyone have direct experience or a reputable source to answer what percentage of password breaches are ...
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Detect when I do brute force attack and block the connection

My server (Ubuntu + LAMP) is infected, as I receive security alerts from the sites attacked from my IP. your Server/Customer with the IP: ********** has attacked one of our servers/partners. The ...
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How much faster does a GPU or FPGA crack an RSA key compared to a CPU?

Are there any significant speed up in time on cracking an RSA key (either brute-force or factoring with general number field sieve) using a GPA or FPGA compared to a CPU? If there is a speed ...
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Are these access.log entries successful wordpress login attempts?

I am hosting some wordpress sites on an apache 2.4 webserver, and I have discovered thousands of entries in my server logs like this: 221.219.219.248 - - [09/Mar/2015:03:29:25 +1300] "GET ...
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Hydra when redirects

I'm using Hydra and I have trouble with this command: hydra 123.123.123.123 http-form-post \ "/se/login:j_username^USER^&j_password=^PASS^&submit=Log+in:/se/invalidLogin" \ -L ...
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Is there an equivalent of an Apple cryptochip in Android devices?

Apple has a cryptochip which, beside managing the encryption keys, tunnels authentication and provides throttling of failed attempts, as well as the ability to trigger a device wipe after several ...
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Connection on port 3387 Event viewer says “authorized”

This event shows up multiple times within a minute like it was being brute-forced, but it says "authorized". My question is: Is there anyway I can see any commands that came in from this connection? I ...
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Random padding in hash functions

In this answer, it was recommended that you add random padding when hashing messages for a trusted timestamp, such as for predictions, in order to avoid dictionary and brute force attacks (at least ...
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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. ...
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Insecure to require numbers in passwords?

Earlier, I went to a site that required a number and special character, and it got me thinking – wouldn't that make the password easier to brute force? If you assume most passwords have around 12 ...
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What alternatives do email services provide when an account is hacked?

I am concerned about how does email services like Yahoo, Gmail, Hotmail etc provide security to their costumers and prevent their account from being compromised. For example, I have seen that if ...
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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?
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Why don't sites implement a system where a wrong password causes a 3 second delay?

I am into bitcoin right now, and the password threats scare me a little... Not so much for me, because I use LastPass and generate new passwords at 20 characters and it includes symbols, upper and ...
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How can i calculate the number of possible passwords?

I have found a flaw in a site where the password reset feature resets passwords in the following format UpperCaseLetter-Number-LowerCaseLetter-Number-LowerCaseLetter-Number-UpperCaseLetter ...
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Can this be a DoS Attack?

When I'm checking my log, I found like 15k events of " PAM service(sshd) ignoring max retries; 6 > 3 " I know this might be normal, and considered as Brute-Force attack, but can it be classified as ...
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Securing AES 128 encrypted ZIPs against brute force attacks

How long would it take to brute force decrypt an AES 128 encrypted zip file if the password is 8 characters long in the range of A-Z, a-z, 1-9? Does it make any difference if .NET's System.Random ...
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Can key files be brute-forced like passwords?

Let's say you use a program like Truecrypt or Keepass which allows you to have a password + key file. I understand that passwords can be brute-forced/dictionary-attacked but is the same true for key ...
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Could using a generated key from an online service be considered a risk?

With some colleagues we're having a debate regarding the randomkeygen.com website. I do think that there is a security risk using the generated keys of this (or any of this kind) website. Why ? ...
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Is there any reason in particular encryption keys aren't arbitrarily large?

It's my understanding that the more bits an encryption key has, the longer it takes to break the encryption. What is the down side of having a larger encryption key or why don't we see keys of size ...
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Known Password Lengths and security considerations

Many people wil often brag about the length of their password, like "yeah nobody is ever going to crack my password cause its 22 characters long." I was thinking, if you knew the exact length of their ...
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Spoofing an NTP server to allow bruteforce on any smartphone

We all know that smartphones (i'll take iPhone as an example) rely on SNTP/NTP servers to update a device's time and date. So, by creating an SNTP server that mimics Apple's server, we can actually ...
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Session Hijacking through sessionId brute-forcing possible?

cookies usually contain a sessionId to keep track of a logged user. What would prevent a malicious user to forge millions of requests with random sessionIds and send them to a server, hoping to ...
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Forgot password to 7-Zip archive

I think I already know the answer to this question, but I thought I'd ask the experts anyway. A few months back, I created a password-protected 7-Zip archive which housed the source code of a simple ...
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is it easier to get the original password if you have multiple hashes of it?

Most users tipically use the same password for multiple applications. Let's say all of these applications hash the password in some way. Would it be easier for an attacker to get the original password ...
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How can I determine whether a website somehow protects against brute force attacks on my password? (assume I can't create an anonymous account)

After the hack of Mat Honan I studied my own laundry list of accounts I have at the numerous web sites I use. There is one fact that stands out: Many of the websites severely restrict the size and ...
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Can using emojis make someone's password safer?

I was just thinking about this the other day, after reading about making safe passwords, you have a few options: The first would be, adding numbers, or something other than just a word ...
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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 can you I detect low frequency brute forcing over multiple connections?

While I realize that servers can easily detect brute forcing strategies via a single I.P, it seems that servers would be vulnerable to a distributed attack from a botnet, with each computer attempting ...
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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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Is using Gmail's browser-based client, more secure than using IMAP?

I never use the same password twice and my passwords are always comprised of a long, random string of letters, numbers and symbols. (with an offline password manager to store each password string) ...
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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 ...
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What are the dangers of exposing weakly protected user accounts bound with a fake shell over ssh?

As anyone running a server can tell from first-hand experience, there are bots trying to constantly brute force their way through with commonly found usernames over SSH. A friend of mine created a ...
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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 ...
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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 ...