Microsoft Issues Biggest Security Patch Yet

Microsoft on Tuesday released a record-setting security patch consisting of 14 bulletins that address 34 vulnerabilities.

Eight of the bulletins are rated "critical" and six are rated "important."

Affected software includes: Microsoft Office, Microsoft Windows, Microsoft Internet Explorer, Microsoft Silverlight, Microsoft XML Core Services and Server Message Block.

In addition, Microsoft is releasing a new security advisory for a privilege escalation vulnerability that affects its Windows Service Isolation feature.

The massive patch is the largest since October, 2009, when Microsoft issued 13 security bulletins covering 34 vulnerabilities.

MS10-046 would bring the total to 15 bulletins but for the fact that it was issued out-of-band last week to provide a fix for a 0-day flaw in LNK files. The vulnerability is currently being exploited by the Stuxnet family of malware.

Wolfgang Kandek, CTO of Qualys, advises IT administrators to patch the vulnerabilities that affect end users and Internet browsing first.

These include: MS10-053, six fixes for Internet Explorer; MS10-055, a Cinepak code vulnerability; MS10-052, a vulnerability in Microsoft's MPEG Layer-3 audio codecs; MS10-060, a vulnerability affecting Silverlight and .Net; MS10-051, a vulnerability in the Internet Explorer MSXML ActiveX component; and MS10-049, a client side HTTPS vulnerability.

The first five of these are all have an Explotability Rating of "1"; the sixth, MS10-049, has an Explotability Rating of "2".

MS10-054 addresses a vulnerability in the SMB protocol.

Joshua Talbot, security intelligence manager for Symantec Security Response, argues that this should be of particular concern to enterprises.

"Not only does it give an attacker system-level access to a compromised SMB server, but the vulnerability occurs before authentication is required from computers contacting the server," he said in an e-mail. "This means any system allowing remote access and not protected by a firewall is at risk."

Josh Abraham, security researcher for Rapid7, concurs, noting in an e-mail that the SMB vulnerability "is potentially the most dangerous vulnerability as it allows unauthenticated attackers to execute arbitrary code on remote machines."