Microsoft's conclusion? It confirmed that the WSUS blocking issue really is a problem after all. The company recommends that IT shops affected by the problem install an update. A description of the problem and link to get the update can be accessed here (Knowledge Base Article 954960).
The update only applies to users of System Center Essentials and System Center Configuration Manager 2007. Those products are the only ones that use WSUS, according to Microsoft's Knowledge Base Article.
The fix to the blocking problem was originally provided on August 1 via the Microsoft Download Center. However, Microsoft revised its Knowledge Base Article yesterday simply to alert users that the update is now available via Microsoft Update. Those who got the update on August 1 don't have to reinstall it.
While the blocking issue seems to be a security issue, that's something that the technicians at Microsoft vigorously contend.
"In this case, Microsoft is communicating an issue that affects your ability to perform updates, including security updates," the Knowledge Base Article states. "Therefore, this advisory does not address a specific security vulnerability; rather, it addresses your overall security."
So it's not a software security issue in the sense of fixing software that's innately insecure. However, if left unfixed, the WSUS problem can wreak havoc by leaving Office 2003 unpatched.
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