Experts: Enterprises must patch Microsoft server bug

Microsoft patches a total of 11 vulnerabilities -- five of them rated critical

Microsoft Tuesday issued six security updates for Windows, Office and the .Net Framework, patching a total of 11 vulnerabilities -- five of them rated critical.

The most serious of the batch is MS07-039, said security analysts who, unlike last month, had no trouble naming that critical update as the one which should be patched first.

"By far, this is the top of the list this month," said Andrew Storms, director of security operations at nCircle Network Security.

MS07-039 patches a pair of bugs in Active Directory in Windows 2000 Server and Windows Server 2003, the two supported server editions of Microsoft's operating system. The most dangerous of the two is a vulnerability in the way Active Directory validates an LDAP (Lightweight Directory Access Protocol) request. According to Microsoft's write-up, "an attacker who successfully exploited this vulnerability could take complete control of an affected system."

"Definitely at the top of today's list," agreed David Dewey, a researcher with IBM Internet Security Systems' X-Force team. "It's definitely exploitable."

Dewey should know, since it was a colleague at Internet Security Systems (ISS), Neel Mehta, who discovered the flaw last summer. "Neel's created proof-of-concept code in-house during the time we worked on this with Microsoft," said Dewey.

"It would certainly be worth the effort" to exploit this, added Storms. "Active Directory is in the center of every Windows network. There's a lot in there, including the group policy objects that set security -- and everything about every user."

Unlike most vulnerabilities, the Active Directory bug can be exploited without any user interaction, and on Windows 2000 Server, the older of the two operating systems, it can be attacked by an anonymous user. Although Windows Server 2003 may look safer at first glance -- an attacker must have valid credentials to exploit the bug on that edition -- looks can be deceiving, said Tom Cross, another X-Force researcher.

"In this case, the authentication requirements become less important," said Cross. "Anyone on the network -- an employee, for example -- would by definition have credentials." Worse, said Cross, is that outside attackers could exploit this without a lot of trouble by bundling an MS07-039 exploit with a multistrike attack that figures on compromising some fraction of enterprise laptops while they're outside the network. Once back inside the enterprise's perimeter, the Active Directory exploit could fire up -- using the credentials of the hijacked notebook -- to grab systems running the supposedly more secure Windows Server 2003.

Two of the remaining five bulletins -- MS07-036 and MS07-040 -- were pegged "critical" by Microsoft, with another two marked "important" and the final update tagged as "moderate."

As usual, Microsoft's monthly updates have been posted to Microsoft Update and Windows Update services, and they can also be retrieved through Windows Server Update Services (WSUS).

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.
Gregg Keizer

Gregg Keizer

Computerworld
Show Comments

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Tom Pope

Dynabook Portégé X30L-G

Ultimately this laptop has achieved everything I would hope for in a laptop for work, while fitting that into a form factor and weight that is remarkable.

Tom Sellers

MSI P65

This smart laptop was enjoyable to use and great to work on – creating content was super simple.

Lolita Wang

MSI GT76

It really doesn’t get more “gaming laptop” than this.

Jack Jeffries

MSI GS75

As the Maserati or BMW of laptops, it would fit perfectly in the hands of a professional needing firepower under the hood, sophistication and class on the surface, and gaming prowess (sports mode if you will) in between.

Taylor Carr

MSI PS63

The MSI PS63 is an amazing laptop and I would definitely consider buying one in the future.

Christopher Low

Brother RJ-4230B

This small mobile printer is exactly what I need for invoicing and other jobs such as sending fellow tradesman details or step-by-step instructions that I can easily print off from my phone or the Web.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?