Ophcrack is a
free open-source
Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...
(
GPL licensed) program that
cracks Windows log-in passwords by using
LM hash
LAN Manager is a discontinued network operating system (NOS) available from multiple vendors and developed by Microsoft in cooperation with 3Com Corporation. It was designed to succeed 3Com's 3+Share network server software which ran atop a h ...
es through
rainbow table
A rainbow table is a precomputed table for caching the outputs of a cryptographic hash function, usually for cracking password hashes. Passwords are typically stored not in plain text form, but as hash values. If such a database of hashed passw ...
s. The program includes the ability to import the hashes from a variety of formats, including dumping directly from the
SAM files of Windows, and can be run via the command line or using the program’s GUI (
Graphical user interface
A graphical user interface, or GUI, is a form of user interface that allows user (computing), users to human–computer interaction, interact with electronic devices through Graphics, graphical icon (computing), icons and visual indicators such ...
). On most computers, ophcrack can crack most passwords within a few minutes.
Rainbow tables for
LM hashes are provided for free by the developers. By default, ophcrack is bundled with tables that allow it to crack passwords no longer than 14 characters using only alphanumeric characters. Available for free download are four Windows XP tables and four Windows Vista tables.
Objectif Sécurité has even larger tables that are intended for professional use. Larger rainbow tables are NTLM hash for cracking
Windows Vista
Windows Vista is a major release of the Windows NT operating system developed by Microsoft. It was the direct successor to Windows XP, released five years earlier, which was then the longest time span between successive releases of Microsoft W ...
/
Windows 7
Windows 7 is a major release of the Windows NT operating system developed by Microsoft. It was Software release life cycle#Release to manufacturing (RTM), released to manufacturing on July 22, 2009, and became generally available on October 22, ...
.
In september 2019 these tables have also been made available for free.
Ophcrack is also available as
Live CD
A live CD (also live DVD, live disc, or live operating system) is a complete booting, bootable computer installation including operating system which runs directly from a CD-ROM or similar storage device into a computer's memory, rather than lo ...
distributions, which automates the retrieval, decryption, and cracking of passwords from a
Windows
Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...
system. One Live CD distribution is available for Windows XP and lower and another for Windows Vista and Windows 7. The Live CD distributions of ophcrack are built with
SliTaz GNU/Linux.
Starting with version 2.3, Ophcrack also cracks
NTLM
In a Windows network, NT (New Technology) LAN Manager (NTLM) is a suite of Microsoft security protocols intended to provide authentication, integrity, and confidentiality to users. NTLM is the successor to the authentication protocol in Microsoft ...
hashes. This is necessary if the generation of the LM hash is disabled (this is default for
Windows Vista
Windows Vista is a major release of the Windows NT operating system developed by Microsoft. It was the direct successor to Windows XP, released five years earlier, which was then the longest time span between successive releases of Microsoft W ...
) or if the password is longer than 14 characters (in which case the LM hash is not stored).
Starting with version 3.7.0, the source code has been moved from SourceForge to GitLab.
See also
*
Aircrack-ng
*
Cain and Abel
In the biblical Book of Genesis, Cain and Abel are the first two sons of Adam and Eve. Cain, the firstborn, was a farmer, and his brother Abel was a shepherd. The brothers made sacrifices, each from his own fields, to God. God had regard for Ab ...
*
Crack
*
DaveGrohl
*
Hashcat
*
John the Ripper
*
L0phtCrack
*
NMap
*
RainbowCrack
RainbowCrack is a computer program which generates rainbow tables to be used in password cracking. RainbowCrack differs from "conventional" brute force crackers in that it uses large pre-computed tables called rainbow tables to reduce the leng ...
References
External links
*
*
*
Ophcrack Online Demo- form to submit hashes and instantly crack passwords
- how to fix if Ophcrack says "no tables found".
OPHCRACK (the time-memory-trade-off-cracker)-
École Polytechnique Fédérale de Lausanne
The École Polytechnique Fédérale de Lausanne (, EPFL) is a public university, public research university in Lausanne, Switzerland, founded in 1969 with the mission to "train talented engineers in Switzerland".
Like its sister institution E ...
Free security software
Password cracking software
Cryptanalytic software
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