Every network administrator needs to recover a lost or unknown password from time to time. Ophcrack uses the rainbow tables method to recover passwords, and it has a brute force module for cracking simple passwords. Operating System: Windows, Linux, OS X.
John the Ripper can crack weak Unix passwords very quickly. It also comes in a paid Pro version. Operating System: Windows, Linux, OS X.
This very popular open source VPN solution offers remote network access to your network with OpenSSL encryption and authentication capabilities. In addition to the open source community version, it also comes in a paid version for enterprises, and it's available as a service through PrivateTunnel. Operating System: Windows, Linux, OS X, others.
This remote control application allows users to interact with a system in one location while using a system in another location. In addition to its telecommuting uses, it's also useful in many help desk situations. Operating System: Windows, Linux.
UltraVNC offers similar capabilities as TightVNC. Key features include file transfer, video driver, optional encryption plugins, MS logon, text chat, viewer toolbar, viewer auto scaling, multiple monitor support, auto reconnection and more. Operating System: Windows.
Replaces: Cisco routers
Used by dozens of Fortune 500 companies, Vyatta allows users to create their own enterprise-grade networking appliance from any x86 system. You can find commercial products based on the same technology at Vyatta.com. Operating System: Linux.
Replaces: Cisco routers
This Linux-based software lets you set up your own router or a Web, FTP, DNS or SSH server. It incorporates firewalling and NAT capabilities. Operating system: Linux.
Replaces the firmware on Lynksys, Buffalo, and other Broadcom-based routers
While the other projects in this category allow you to create your own routers from standard PCs, this project is a replacement for the firmware on routers you may already own, specifically Linksys' WRT54G/GL/GS, Buffalo WHR-G54S/WHR-HP-G54 and other Broadcom-based routers. It includes some more advanced management capabilities, raises the maximum connections for P2P and enables additional wireless features.
BackTrack's website describes it as "a Linux-based penetration testing arsenal that aids security professionals in the ability to perform assessments in a purely native environment dedicated to hacking." It's won numerous awards and has been downloaded more than 4 million times. Operating System: Linux.
This well-known penetration testing tool simplifies network discovery and vulnerability verification. In addition to the free community version, it also comes in paid pro and express versions that add more capabilities. Operating System: Windows, Linux.
Often used alongside Metasploit, Nexpose offers vulnerability scanning for very small organizations or individuals. It also comes in paid express, consultant and enterprise versions. Operating System: Windows, Linux.
This powerful network scanner helps with numerous administrative tasks, such as network inventory, managing upgrades and monitoring uptime, as well as with performing security audits. It's very flexible, portable and it's won numerous awards. Operating System: Windows, Linux, OS X.
The "world's most advanced open source vulnerability scanner and manager," OpenVAS is a framework with several tools for security testing and management. As of May 2012, it now includes more than 25,000 network vunlerability tests. Operating System: Windows, Linux, OS X.
Short for "Security Auditor's Research Assistant," Sara integrates with the National Vulnerability Database (NVD) and performs SQL injection and XSS tests. It's no longer under active development, but you can still download the code from this link. Operating System: Windows, Linux, OS X.
This content filtering tool uses phrase matching, PICS filtering and URL filtering to block objectionable material from your network. Highly flexible, it allows the user to define what is an what is not objectionable, with the default settings designed to be appropriate for young children. Operating System: Linux, OS X.