One of the security bulletins has been rated as critical by
IT security and control firm Sophos has advised companies to
consider the benefits of Network Access Control (NAC) in light of
the announcement of the latest critical security patches from
As part of its monthly "Patch Tuesday" schedule Microsoft has
issued two new bulletins (one of them described as "critical")
about security vulnerabilities in its software. The vulnerabilities
cover a number of different versions of the Windows operating
system, but do not include Windows Vista.
The more serious of the bulletins tackles a remote code
execution vulnerability in the way that the Windows shell handles
maliciously-crafted URIs. This is the same flaw that Sophos experts
discovered was being exploited by the widely-distributed PDFex Trojan horse at the
of last month.
Sophos recommends that organizations roll-out the patches as a
matter of urgency, as some of them could enable hackers to access
data on a vulnerable PC or run malicious code such as a worm.
Network Access Control enables companies to control who and what
is allowed onto their network; blocking unauthorized users,
controlling guest access, and ensuring compliance with a business's
security policy. By implementing NAC firms reduce the risk of
unauthorized, guest, non-compliant, or infected systems
compromising the network, ensuring that only correctly secured
computers gain network access.
"It doesn't take a rocket scientist to realise that it's
critical for businesses and home users to have the latest security
patches in place. Leaving your computers unpatched means that you
are risking becoming the victim of a hacker attack," said Graham Cluley, senior
technology consultant at Sophos. "Network Access Control
can help organizations enforce security policies, ensuring that any
non-compliant device is locked down and unable to jeopardize the
Home users of Microsoft Windows can visit update.microsoft.com to have their systems scanned for
Microsoft security vulnerabilities.
Sophos suggests that every IT manager responsible for security
should consider subscribing to vulnerability mailing lists such as
that operated by Microsoft at www.microsoft.com/technet/security/bulletin/notify.mspx.
Sophos continues to recommend companies protect their desktops
and servers with automatically updated
protection against viruses, spyware, hackers, and spam.