75 Top Open Source Security Apps

ALSO SEE: 26 Open Source Security Apps with Commercial Support

AND: 2008: The Top 75 Open Source Security Apps

According to the FBI, cybercrime complaints rose 20 percent in 2009, and victims lost $559 million, more than double the year before.

With online crime on the rise, it's more important than ever to protect your systems. But you don't have to pay a lot of money for security. The open source community continues to produce (and maintain) excellent tools that fulfill a wide variety of security needs.

This year, we've once again updated our list of top open source security apps. While the list isn't exhaustive by any means, we tried to include many of the best tools in a variety of categories. We dropped a few projects from last year's list that have gone inactive or closed source, and we've added a few newcomers that are worth your consideration.

Anti-Virus/Anti-Malware

1. ClamAV

Probably the best-known and most popular open-source anti-virus engine, ClamAV powers numerous commercial and open-source security apps. The version here runs on Linux/Unix, but it's also available with a variety of front-ends for other operating systems (see below). Operating System: Linux.

2. ClamWin Free Antivirus

As you might expect from the name, this app lets you use ClamAV with Windows. The latest version supports Windows 7, and offers improved speed over earlier releases. Operating System: Windows.

3. ClamTk

Like ClamWin, ClamTK provides a front end for the ClamAV engine, this time for the Linux OS. It allows you to schedule system scans, but it does not provide real-time scanning for incoming files. Operating System: Linux.

4. Rootkit Hunter

This no-frills tool scans for rootkits and other malware on Linux system. While it does not provide live or scheduled scanning, the Web site explains how to set up your system to scan daily. Operating System: Linux, Unix.

5. No Autorun

Worried that the thumb drive you're about to insert into your USB port might contain malware? This utility blocks any viruses on the drive from running automatically. Operating System: Windows.

Anti-Spyware

6. Nixory

If you use Firefox, Nixory can help protect you from unwanted cookies and spyware. Importantly, it works alongside your existing anti-virus and firewall solutions. Operating System: OS Independent.

Application Firewall

7. AppArmor

Included with openSUSE and SUSE Linux Enterprise, this application firewall from Novell uses policy-based profiles to control who can access various applications. It protects you from malware that exploits application flaws and effectively contains unwanted programs. Operating System: Linux.

8. ModSecurity

ModSecurity provides an outer layer of protection against attacks. The latest version, released in February 2010, adds new features like parallel text matching, Geo IP resolution, credit card number detection, support for content injection, automated rule updates, scripting, and more. Hardened appliances and commercial support are available from project developer Breach Security. Operating System: OS Independent.

Data Removal

9. BleachBit

In addition to "shredding" deleted files so that they cannot be recovered, BleachBit cleans up your cache, cookies, Internet history, logs, temp files, etc. for faster performance and greater privacy. Operating System: Windows, Linux.

10. Eraser

Just because you delete a file doesn't mean it's gone. Eraser makes sure no one can recover your old files by writing over them with random data. Operating System: Windows

11. Wipe

Wipe does the same thing as Eraser, but it works on Linux. Operating System: Linux.

12. Darik's Boot and Nuke

Before you give away or donate an old computer, make sure you completely erase the hard drive. How? Just run Darik's Boot and Nuke (DBAN) from a boot disk. Operating System: OS Independent.

13. Disk Cleaner

This small utility cleans all the “junk” out of your temporary files, cache etc. It deserves inclusion in our security tools because it's also handy for protecting your privacy when using public machines. Operating System: Windows

Developer Tools

14. OWASP

The “Open Web Application Security Project” includes a number of documents, applications, and tools for developers concerned about app security. Key projects include WebGoat, ESAPI Security Library for Java, and numerous standards and guides. Operating System: OS Independent

15. php ClamAV

This package allows you to incorporate the ClamAV engine into your PHP5 scripts. Operating system: Linux

16. MCrypt

This replacement for the Unix crypt allows developers to add a wide range of encryption functions to their code, even if they don't know a lot about cryptography. The Web site contains a list of supported algorithms that are included in the Libmcrypt library. Operating System: Windows, Linux, Unix.

Encryption

17. AxCrypt

Downloaded more than a million times, AxCrypt bills itself as the "leading open source file encryption software for Windows." Simply right-click on a file in Windows Explorer to encrypt it, and a double-click decrypts data. Operating System: Windows.

18. Gnu Privacy Guard

This is Gnu's implementation of the OpenPGP standard for digitally signing and de-crypting information. Although this app works from the command line, you can find links to GUI front-ends on the site. Operating System: Windows, Linux, OS X..

19. Mac GNU Privacy Guard

As you might expect, this app ports GnuPG for a Mac. Note that you will need to see the detailed instructions for installation with Snow Leopard. Operating System: OS X.

20. gpg4win

And this is a version of Gnu Privacy Guard (GPG) for Windows. Formerly available only in German, the program and documentation have been translated for English speakers. Operating System: Windows.

21. PeaZip

Primarily a compression utility, PeaZip can also encrypt files using a variety of different algorithms. It's ideal for archiving files or protecting and compressing large files for e-mail. It's also available in a portable version for USB thumb drives. Operating System: Windows, Linux.

22. Steghide

If you really want to feel like a spy, you can use Steghide to conceal hidden messages in audio or text files. It works with JPEG, BMP, WAV and AU files. Operating System: OS Independent.

23. MailCrypt

This app applies PGP or GnuPGP encryption to your e-mail and Internet usage. If you use Windows NT, be sure to read the warning note on the Web site. Operating System: OS Independent.

24. Crypt

Designed for speed and minimum impact on your system, Crypt doesn't require installation and won't mess up any of your registry keys. Its lightweight and encrypts and decrypts files quickly and easily. Operating System: Windows.

25. NeoCrypt

This Windows-only encryption utility boasts an easy-to-use interface as well as right-click integration with Windows Explorer. It supports ten popular encryption algorithms and offers the option of batch file encryption if you need to encrypt a number of files at once. Operating System: Windows.

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