Companies should consider the benefits of Network Access Control (NAC) to ensure that computers are adhering to corporate IT security policy, in light of a number of new security patches being issued yesterday by Microsoft.

As part of its monthly "Patch Tuesday" schedule, Microsoft is issuing four new bulletins (one of them described as "critical") outlining a number of different security vulnerabilities in its products, including its Windows 2000 operating system and Windows Live Messenger.
All organisations should roll-out these patches as a matter of urgency, as some of them could enable hackers to access data on a vulnerable PC or run malicious code.  However, many firms could still be at risk if they allow guests, business partners or customers to bring unpatched machines into the company and connect to the network.
According to experts at Sophos, a large number of companies face an ongoing struggle to ensure that all internal devices are successfully patched against emerging vulnerabilities. This is because some machines may be incorrectly configured to receive updates, while others may not be connected to the network at the time of the roll-out.
Installing the latest Microsoft security patches may sound straightforward, but for a lot of companies it's easier said than done, particularly if you have a regular stream of visitors connecting to your network, says Brett Myroff, CEO of master Sophos distributor, NetXactics.
"It really makes little difference whether it's an employee's desktop PC or a customer's laptop – an unpatched machine represents a possible avenue for a cyber attack."
He adds that Network Access Control can help prevent this from becoming a reality by giving businesses the ability to control who and what is connecting to a network.  
"If a machine hasn't had the correct patches installed, you can prevent it from causing any harm to the rest of your organisation by blocking its access to the network, or quarantining the machine until it conforms to company IT policy."
Home users of Microsoft Windows can visit 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
The cmpany also recommends that companies protect themselves with a consolidated solution which can control network access and defend against the threats of spam, hackers, spyware and viruses.