Microsoft made a second attempt to cleanly patch an "important" security flaw in its Active Directory Federation Services technology on Monday - days after yanking the original update for causing stability problems.
The original MS13-066 upgrade caused the active directory service to stop working entirely in some cases. The second iteration of the security patch is, we are assured, a much more stable fix.
Bear in mind it should applied to server software usually run within enterprise environments to provide corporate users with Single Sign-On access to internet applications and the like.
"As the vulnerability it was attempting to fix had only been privately reported, and was not believed to be being exploited in the wild, it’s possible that the fix had actually turned into a bigger problem than the one it was attempting to solve – on Windows Server 2008 systems at least," notes security watcher Graham Cluley.
The withdrawal of security updates by Redmond is rare but not unprecedented: August's Patch Tuesday suffered a similar cock-up, forcing Redmond to withdraw a dodgy update for Exchange Server 2013 after it emerged the critical security patch broke the mail indexing service. MS13-061 worked fine on Exchange 2007 and 2010 but not on the latest version of Microsoft's email server software.
The update grapples three vulnerabilities in Microsoft Exchange that stem from bugs in the third-party library Outside In; this is licensed from Oracle and allows Web Access users to view PDF files and such stuff. Exchange Server 2013 users are advised to turn off the functionality as a workaround pending the availability of a working security update. ®