Microsoft Patches Its Patches

Among Microsoft's three Patch Tuesday releases today is a re-release of a re-released Internet Explorer patch (See IE Patch Created New Vulnerability.), as well as a new patch for a Windows server patch.

Got that? The first is basically a third round patch for Internet Explorer, after researchers found yet another bug in the initial patch, MS06-042. Microsoft did not include the two new patches among its three new updates in the standard security bulletins. "The most important patch of this group is the MS06-042 IE update," says Robert Enderle, principal analyst with the Enderle Group.

eEye Digital Security found this latest bug as well as the first one, and it's a similar type of hole, says Marc Maiffret, CTO and chief hacking officer for eEye. "It was déjà vu, but this time the specific functionality it was crashing wasn't widely used in many Websites," he says. "And we didn't see anyone talking about it much, so we didn't rush to do an alert this time."

The bug compromises the user's machine if he or she goes to a link to the infected Website, says Maiffret, whose company was under fire from Microsoft last month for disclosing the first buggy patch before the software giant acknowledged and patched it. (See When to Disclose.)

The second patched patch was for MS06-040, for holes in Windows Server service that also left the door open for an attacker to execute remote code. Microsoft rated both patch patches as "critical."

And among today's three regular patches was a "critical" vulnerability in Publisher 2000 MS06-054, that lets an attacker execute code remotely via Publisher. It's also rated "important" for Publisher 2002 and 2003, but the scope of this vulnerability is limited to mostly consumer and small business users that run Publisher, security experts say.

Maiffret says the Publisher vulnerability is part of the trend toward attacks on client applications. "The more they see these vulnerabilities, companies need to ask what they are doing to protect each desktop beyond perimeter firewalls."

Gunter Ollmann, director of Internet Security Systems' X-Force, says it's unlikely there will be much exploitation of this bug.

The MS06-052 patch, rated "important" by Microsoft, fixes a vulnerability in the Reliable Multicast Program that's susceptible to a denial of service attack. "This one is more important for enterprises," X-Force's Ollmann says. It would affect those companies that use the MSNQ protocol for messaging systems on in-house applications, he says, but that's not so widespread.

And the MS06-053 patch for the Windows Indexing Service, ranked as "moderate," fixes a cross-site scripting vulnerability. "I would rank this as a low-risk vulnerability," says X-Force's Ollmann. "It's more a side note in the 2,000 to 3,000 XSSes that are disclosed each year."

Missing among the patches was one for the recent zero-day Word bug (See Zero-Day Exploit Targets Word.), but security researchers weren't expecting it to come this soon. Amol Sarwate, manager of vulnerability research lab at Qualys, says this one will likely come in a separate release. "We expect that the potential exists for an intermittent patch to be released prior to the next scheduled release to address this flaw, highlighting an increasing trend of Microsoft being forced to break its patch cycle."

Security experts and Microsoft users alike breathed a collective sigh of relief last week when Microsoft said it would release just three security updates. (See Microsoft's Patch 'Lite' Tuesday.)

The next patch day is October 10.

— Kelly Jackson Higgins, Senior Editor, Dark Reading