By Tom Bowers
September 10, 2007
In areas such as CRM software and portals, open source gained a foothold
because users were willing to compromise -- less could be more, because
the price was right. In security, open source rushed in because
commercial vendors fell down on the job. As security problems in the
enterprise outstripped the capabilities of commercial solutions, a
number of talented security researchers stepped into the breach via the
open source model.
From folks such as Renaud Deraison of Nessus to Martin Roesch of Snort,
great security tools poured forth to the enterprise. There are now
thriving open source security projects in anti-virus, anti-spam,
personal and application firewalls, VPNs, IDS/IPS, wireless security,
vulnerability assessment, and penetration testing to name but a few.
In network vulnerability assessment, our Bossie winner, Nessus, stands
alone. The granddaddy of all security tools, Nessus combines an
up-to-the-minute vulnerability engine and testing controls, making it an
essential member of the toolbox in both well-funded and cash-strapped
security organizations. It tests all aspects of a target including the
operating system, ports, services, and applications, and it scores
consistently as the top security tool based on professional security
tester reviews. Reports can be lengthy, but they're comprehensive.
Nessus shows you where intruders might get in. Snort, which takes our
Bossie for intrusion prevention, can stop them from doing so. Snort
performs real-time traffic analysis and packet logging. In addition to
classic protocol analysis, Snort now also performs content monitoring.
Its rules language has evolved light-years beyond the version available
when Snort was first released. And like Nessus, Snort is at the top of
the heap in community support. The Snort project has spawned a range of
add-on projects such as ACID (Analysis Console for Intrusion Databases),
SnortSnarf, Swatch, and SnortCenter. These add-ons are needed for
reporting and centralized control of multiple Snort boxes; Snort itself
is strictly the detection and prevention engine.
In the case of anti-virus, one open source solution stands alone,
ClamAV. ClamAV was recently purchased by Sourcefire, the owners of
Snort. As with most projects on this distinguished list, ClamAV runs on
Linux and Unix, and it was designed primarily for e-mail gateways. Virus
signature updates are frequent and the detection engine is fast. ClamAV
works well with Spamassassin within the MIMEDefang filtering framework
for e-mail servers.
Our Bossie winner for anti-spam is the ubiquitous Spamassassin.
Powerful, extensible, and effective, Spamassassin uses a trainable
neural network engine to identify spam and minimize false positives, in
addition to the classic techniques of blacklisting and Bayesian
Snatching our Bossie for best firewall is IPCop. IPCop is a complete
Linux distribution with the sole purpose of network protection. Think of
it as a Linux computer with one task: imposing security policies on
network traffic. A competing project, SmoothWall, similarly turns any
old PC into a high-functioning firewall appliance, but the Web
management interface of IPCop is a bit more refined and thus edged out
Not to be outdone by the private sector, the exceptionally talented
folks at the NSA created a superior application firewall called SELinux.
The special sauce of this Linux distribution is a mandatory access
control architecture for the OS kernel and major subsystems that keeps
every process in check, ensuring that the action of one process cannot
flow into another. Even the superuser is placed in isolation. A worthy
competitor is Novell's open source AppArmor project, an
easy-to-configure application firewall aimed exclusively at Suse
distributions. SELinux continues to be better supported by the security
community, and it forms the basis for a flexible security solution
(versus a simple secure operating system). SELinux takes the Bossie.
OpenVPN, our Bossie winner for best SSL VPN, is the open source champion
of secure connectivity. OpenVPN simply outshines its competition. It can
be used to secure site to site links, remote access connections, and
Wi-Fi networks, providing load balancing and fail-over capabilities. It
runs on a wide range of operating systems and is supported by numerous
open source projects and commercial products. And OpenVPN supports all
ciphers and key sizes supported by OpenSSL, giving it tremendous
Although not an application per se, the OSSTMM (Open Source Security
Testing Methodologies Manual) is a phenom in the security world. The
OSSTMM project provides an entire testing framework for security
throughout the enterprise, including physical security, information
security, Internet and wireless security, even security against fraud
and social networking attacks. The OSSTMM provides a method for
quantifying risk and an excellent foundation for security testing best
practices. The project offers testing templates, intense community
support, and a first-rate architect in Pete Herzog, scoring our Bossie
for security testing best practices.
Tom Bowers is a contributing editor to the InfoWorld Test Center and
managing director of Security Constructs.
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