We're very impressed by the collective smarts of the security community and we highly recommend reading the whole list and investigating any tools you are unfamiliar with. Click any tool name for more details on that particular application, including the chance to read (and write) reviews. Many site elements are explained by tool tips if you hover your mouse over them. Enjoy!
WebGoat is a deliberately insecure J2EE web application maintained by OWASP designed to teach web application security lessons. In each lesson, users must demonstrate their understanding of a security issue by exploiting a real vulnerability in the WebGoat application. For example, in one of the lessons the user must use SQL injection to steal fake credit card numbers. The application is a realistic teaching environment, providing users with hints and code to further explain the lesson.
Read 1 review.
Latest release: version 5.3 RC1 on Nov. 1, 2009 (10 years, 11 months ago).
HijackThis inspects a computer’s browser and operating system settings to generate a log file of its current state. It can selectively remove unwanted settings and files. Its main focus is on web browser hijacking. It is a freeware utility originally written by Merijn Bellekom but now distributed by Trend Micro.
Read 2 reviews.
Latest release: version 2.0.5 on May 18, 2013 (7 years, 4 months ago).
The Social Engineer Toolkit incorporates many useful social-engineering attacks all in one interface. The main purpose of SET is to automate and improve on many of the social-engineering attacks out there. It can automatically generate exploit-hiding web pages or email messages, and can use Metasploit payloads to, for example, connect back with a shell once the page is opened.
Read 82 reviews.
Malwarebytes' Anti-Malware is a malware scanner for Windows. The authors claim to use a variety of technologies to find malware undetectable by other malware scanners. There is a free trial with limited options and a supported full version with the ability to run scheduled scans.
Read 7 reviews.
Latest release: version 22.214.171.1247 on June 29, 2015 (5 years, 3 months ago).
Netsparker is a web application security scanner, with support for both detection and exploitation of vulnerabilities. It aims to be false positive–free by only reporting confirmed vulnerabilities after successfully exploiting or otherwise testing them.
Read 7 reviews.
Latest release: version 126.96.36.199 on Feb. 10, 2011 (9 years, 7 months ago).
KeePass is a password manager. It stores many passwords which are unlocked by one master password. The idea is to only have to remember one high-quality password, and still be able to use unique passwords for various accounts. It has a feature to automatically fill in passwords in web forms.
Read 5 reviews.
Latest release: version 1.29 on April 3, 2015 (5 years, 6 months ago).
Wireshark (known as Ethereal until a trademark dispute in Summer 2006) is a fantastic open source multi-platform network protocol analyzer. It allows you to examine data from a live network or from a capture file on disk. You can interactively browse the capture data, delving down into just the level of packet detail you need. Wireshark has several powerful features, including a rich display filter language and the ability to view the reconstructed stream of a TCP session. It also supports hundreds of protocols and media types. A tcpdump-like console version named tshark is included. One word of caution is that Wireshark has suffered from dozens of remotely exploitable security holes, so stay up-to-date and be wary of running it on untrusted or hostile networks (such as security conferences).
Read 47 reviews.
Latest release: version 1.12.7 on Aug. 12, 2015 (5 years, 1 month ago).
sqlmap is an open source penetration testing tool that automates the process of detecting and exploiting SQL injection flaws and taking over of back-end database servers. It comes with a broad range of features, from database fingerprinting to fetching data from the DB and even accessing the underlying file system and executing OS commands via out-of-band connections. The authors recommend using the development release from their Subversion repository.
Read 16 reviews.
Latest release: version 0.9 on April 11, 2011 (9 years, 5 months ago).
Ophcrack is a free rainbow-table based cracker for Windows passwords (though the tool itself runs on Linux, Windows, and Mac). Features include LM and NTLM hash cracking, a GUI, the ability to load hashes from encrypted SAM recovered from a Windows partition, and a Live CD version. Some tables are provided as a free download but larger ones have to be bought from Objectif Sécurité.
Read 10 reviews.
Latest release: version 3.6.0 on June 4, 2013 (7 years, 3 months ago).
Fiddler is a Web Debugging Proxy which logs all HTTP(S) traffic between your computer and the Internet. Fiddler allows you to inspect all HTTP(S) traffic, set breakpoints, and "fiddle" with incoming or outgoing data. Fiddler includes a powerful event-based scripting subsystem, and can be extended using any .NET language.
Read 4 reviews.
Latest release: version 188.8.131.52 on July 23, 2015 (5 years, 2 months ago).
Kismet is a console (ncurses) based 802.11 layer-2 wireless network detector, sniffer, and intrusion detection system. It identifies networks by passively sniffing (as opposed to more active tools such as NetStumbler), and can even decloak hidden (non-beaconing) networks if they are in use. It can automatically detect network IP blocks by sniffing TCP, UDP, ARP, and DHCP packets, log traffic in Wireshark/tcpdump compatible format, and even plot detected networks and estimated ranges on downloaded maps. As you might expect, this tool is commonly used for wardriving. Oh, and also warwalking, warflying, and warskating, etc.
Read 3 reviews.
Latest release: version Kismet-2013-03-R1b on April 8, 2013 (7 years, 5 months ago).
Core Impact isn't cheap (be prepared to spend at least $30,000), but it is widely considered to be the most powerful exploitation tool available. It sports a large, regularly updated database of professional exploits, and can do neat tricks like exploiting one machine and then establishing an encrypted tunnel through that machine to reach and exploit other boxes. Other good options include Metasploit and Canvas.
Read 20 reviews.
Latest release: version 12 on Aug. 8, 2011 (9 years, 1 month ago).
Tamper Data is an add-on for Firefox that lets you view and modify HTTP requests before they are sent. It shows what information the web browser is sending on your behalf, such as cookies and hidden form fields. Use of this plugin can reveal web applications that trust the client not to misbehave.
Read 3 reviews.
Latest release: version 10.1.1 on Feb. 11, 2010 (10 years, 7 months ago).
NBTScan is a program for scanning IP networks for NetBIOS name information (similar to what the Windows nbtstat tool provides against single hosts). It sends a NetBIOS status query to each address in a supplied range and lists received information in human readable form. For each responded host it lists IP address, NetBIOS computer name, logged-in user name and MAC address. The original nbtscan was written by Alla Bezroutchko. Steve Friedl has written an alternate implementation.
Read 4 reviews.
Latest release: version 1.5.1 on June 1, 2003 (17 years, 4 months ago).
This simple utility reads and writes data across TCP or UDP network connections. It is designed to be a reliable back-end tool to use directly or easily drive by other programs and scripts. At the same time, it is a feature-rich network debugging and exploration tool, since it can create almost any kind of connection you would need, including port binding to accept incoming connections.
Ettercap is a suite for man in the middle attacks on LAN. It features sniffing of live connections, content filtering on the fly and many other interesting tricks.
It supports active and passive dissection of many protocols (even ciphered ones) and includes many feature for network and host analysis.
Read 34 reviews.
Latest release: version 0.8.2-Ferri on March 14, 2015 (5 years, 6 months ago).
Burp Suite is an integrated platform for attacking web applications. It contains a variety of tools with numerous interfaces between them designed to facilitate and speed up the process of attacking an application. All of the tools share the same framework for handling and displaying HTTP messages, persistence, authentication, proxies, logging, alerting and extensibility. There is a limited free version and also Burp Suite Professional ($299 per user per year).
Read 27 reviews.
Latest release: version 1.4.01 on June 3, 2011 (9 years, 4 months ago).
Metasploit took the security world by storm when it was released in 2004. It is an advanced open-source platform for developing, testing, and using exploit code. The extensible model through which payloads, encoders, no-op generators, and exploits can be integrated has made it possible to use the Metasploit Framework as an outlet for cutting-edge exploitation research. It ships with hundreds of exploits, as you can see in their list of modules. This makes writing your own exploits easier, and it certainly beats scouring the darkest corners of the Internet for illicit shellcode of dubious quality. One free extra is Metasploitable, an intentionally insecure Linux virtual machine you can use for testing Metasploit and other exploitation tools without hitting live servers.
Metasploit was completely free, but the project was acquired by Rapid7 in 2009 and it soon sprouted commercial variants. The Framework itself is still free and open source, but they now also offer a free-but-limited Community edition, a more advanced Express edition ($5,000 per year per user), and a full-featured Pro edition. Other paid exploitation tools to consider are Core Impact (more expensive) and Canvas (less).
Netstumbler is the best known Windows tool for finding open wireless access points ("wardriving"). They also distribute a WinCE version for PDAs and such named MiniStumbler. The tool is currently free but Windows-only and no source code is provided. It uses a more active approach to finding WAPs than passive sniffers such as Kismet or KisMAC.
Read 3 reviews.
Latest release: version 0.4.0 on April 1, 2004 (16 years, 6 months ago).
The authors of TrueCrypt abandoned the project in May 2014. While many still use the software, there are several forks and alternatives that are striving to take its lofty place.
TrueCrypt is an excellent open source disk encryption system for Windows, Mac, and Linux systems. Users can encrypt entire filesystems, which are then on-the-fly encrypted/decrypted as needed without user intervention beyond initially entering their passphrase. A clever hidden volume feature allows you to hide a second layer of particularly sensitive content with plausible deniability about whether it even exists. Then if you are forced to give up your passphrase, you give them the first-level secret. That only allows them access to the innocuous material you have there, without proving that a second level key even exists.
Read 5 reviews.
Latest release: version 7.2 on May 28, 2014 (6 years, 4 months ago).
skipfish is an active web application security reconnaissance tool. It prepares an interactive sitemap for the targeted site by carrying out a recursive crawl and dictionary-based probes. The resulting map is then annotated with the output from a number of active (but hopefully non-disruptive) security checks. The final report generated by the tool is meant to serve as a foundation for professional web application security assessments.
Read 2 reviews.
Latest release: version 2.10b on Dec. 4, 2012 (7 years, 10 months ago).
Alienvault OSSIM stands for Open Source Security Information Management. Its goal is to provide a comprehensive compilation of tools which, when working together, grant network/security administrators with a detailed view over each and every aspect of networks, hosts, physical access devices, and servers. OSSIM incorporates several other tools, including Nagios and OSSEC HIDS.
Read 2 reviews.
Latest release: version 5.0.3 on June 2, 2015 (5 years, 4 months ago).
L0phtCrack attempts to crack Windows passwords from hashes which it can obtain (given proper access) from stand-alone Windows workstations, networked servers, primary domain controllers, or Active Directory. In some cases it can sniff the hashes off the wire. It also has numerous methods of generating password guesses (dictionary, brute force, etc). LC5 was discontinued by Symantec in 2006, then re-acquired by the original L0pht guys and reborn as LC6 in 2009. For free alternatives, consider ophcrack, Cain and Abel, or John the Ripper.
Read 7 reviews.
Latest release: version 6.0.11 on Jan. 9, 2011 (9 years, 8 months ago).
Splunk is a tool to search, report, monitor and analyze real-time streaming and historical IT data. It collects logs from a variety of sources and makes them searchable in a unified interface.
Read 6 reviews.
Latest release: version 4.1.7 on Feb. 14, 2011 (9 years, 7 months ago).
Nikto is an Open Source (GPL) web server scanner which performs comprehensive tests against web servers for multiple items, including over 6400 potentially dangerous files/CGIs, checks for outdated versions of over 1200 servers, and version specific problems on over 270 servers. It also checks for server configuration items such as the presence of multiple index files, HTTP server options, and will attempt to identify installed web servers and software. Scan items and plugins are frequently updated and can be automatically updated.
Read 74 reviews.
Latest release: version 2.1.4 on Feb. 20, 2011 (9 years, 7 months ago).