Contents
What can I crack with John the Ripper?
What is John the Ripper Used for?
- UNIX crypt(3)
- Traditional DES-based.
- “bigcrypt”
- BSDI extended DES-based.
- FreeBSD MD5-based (linux and Cisco IOS)
- OpenBSD Blowfish-based.
- Kerberos/AFS.
- Windows LM (DES-based)
Is John the Ripper safe?
Safety? Well, what about it? John the Ripper is just a normal program — it has the same privileges as the user running it. Under Unix systems, regular users cannot read the shadow file (the file storing encrypted passwords; all modern Unixes use shadow passwords).
How long does it take John the Ripper to crack a password?
“Single crack” mode runs typically take from under a second to one day (depending on the type and number of password hashes).
Is it illegal to use a password cracker?
Password managers store passwords of any length and can regularly generate new passwords without the user having to bother to remember them. By the way, in case you’re wondering why password-cracking programs aren’t illegal, it’s because there are perfectly valid and legal reasons to use them.
Can John the Ripper crack any password?
John the Ripper can also crack UNIX/Linux passwords. You need root access to your system and to the password (/etc/passwd) and shadow password (/etc/shadow) files.
What is John the Ripper used for?
John the Ripper is often used in the enterprise to detect weak passwords that could put network security at risk, as well as other administrative purposes.
John the Ripper is a perfectly safe program to install and run, as most popular UNIX tools. If you are running a multi-user system, you should make sure you are shadowing your password file such that the hashes are not visible; however even if you are not, not installing John will not prevent a malicious user from running John on their own…
How does John the Ripper work?
John the Ripper is a password cracking tool capable or breaking a variety of hash types. When combined with a hefty word list such as the infamous rockyou.txt, the tool can make short work of simple passwords. John the Ripper determines the hash type of the password file and then attempts to find a match for those hashes.