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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Do you need more than 128-bit entropy?

UUID uses 128-bit numbers. Currently it is not feasible to randomly produce two UUIDs that are the same. Does that mean 128 bits of entropy is suitable for all cryptographic operations? I would ...
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How can i calculate the number of possible passwords? [closed]

I have found a flaw in a site where the password reset feature resets passwords in the following format [A-Z][0-9][a-z][0-9][a-z][0-9][A-Z] Eg: A0b1c2D I'm trying to determine how many possible ...
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Is a password easier to brute force if it contains a repeating pattern?

My question is different from this previous question: Does repeating one word to form a password result in a similar pattern in its encrypted format?. I'm specifically wondering about brute force ...
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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 ...
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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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Securely displaying hidden integers with MD5

A system I'm studying uses the following mechanism: a 19-digit integer is hashed via the MD5 algorithm and the salt of the integer is shown in plain sight to the user before they take an irreversible ...
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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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Is login limiting still needed if we employ multi-factor authentication?

The status quo is that most online websites limit login attempts per IP address, or even per account since some attackers possess huge amounts of IP addresses. Removing login limits would have 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 advantage,...
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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 we protect signup APIs from brute force registration?

This is a general question but its prompted by a fairly open API I have for a file storage service that needs to have its front door better locked down. We have an API like POST '/signup' that just ...
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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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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 ...
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Having a list of hashes for the same password compromise the security of the password?

An attacker want's access to a specific account, he doesn't know the password. It's a high entropy password. +128bits The attacker has the hash for the password (Assuming OWASP suggested bcrypt with ...
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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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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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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 ...
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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 ...
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Does brute-force time depend on the length of a password only? [duplicate]

If a password is +30 characters long but contains words from the dictionary, is it less secure than a 10-character password that is !@#$#%$^%$, for example?
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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 ...
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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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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 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)?
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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 ...
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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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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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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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Is single iteration SHA-256 safe enough for hashing 128bit random number API keys?

I implemented this kind of authentication for my REST API, is this secure and is my logic sound? I am primarily curious about the SHA-256 hash & iterations = 1 aspect. I have omitted some details ...
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Two factor brute force protection

If I implement two factor authentication using TOTP, I (obviously) have to protect against simple brute force attacks of the TOTP value. If I ask for the TOTP value after successful password login, ...
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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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Username Enumeration as a Threat

I have found a Username Enumeration Vulnerability through which I am able to determine whether a particular user is registered with that site. While trying to brute force, after 5 attempts it asks for ...
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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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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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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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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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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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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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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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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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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 ...
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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 ...
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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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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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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 ...
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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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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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How would someone attack a not truly random secret produced by a human?

Especially in cryptocurrencies you often hear people say that private key/seeds should not be typed "randomly" by humans, but rather use a truly random number generator. I understand, that humans ...
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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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