Credits to Tehnoon Raza
The September Security Bulletin will have SharePoint security updates with a security rating of “Important”.
Both 2007 and 2010 versions will be affected including Office Web Apps. When updates are pushed out to servers without the administrators noticing, this can cause SharePoint to stop working because the updates are installed but not running PSConfig afterwards. PSConfig must be run after update installations!
The known issues in short:
SharePoint 2010 Issues:
Issue #1- Users unable to browse Publishing sites
Issue #2- Unable to Manage User Profile Service Application
For more details and also for information on current known issues related to the security updates, please visit Tehnoon’s excellent post here!
Security Bulletin MS11-074 - Vulnerabilities in Microsoft SharePoint Could Allow Elevation of Privilege (2451858)
Complete summary of all known issues affecting SharePoint 2010 and MOSS 2007 are described in the kb article 2451858.
MS11-074: Description of the security update for SharePoint Server 2010 (pplwfe): September 13, 2011
MS11-074: Description of the security update for SharePoint Workspace 2010: September 13, 2011
Find also some updates and Info's on my fellows blog, "Update on September Security Bulletin (MS11-074) and SharePoint 2010 Issues", by Stefan Goßner
Does the Aug 30 cumulative for WSS3 include the above security update?
As far as I know, it is inside the August CU for SPS 2010 so I would assume, that it might be as well in the WSS August CU but have not verified yet.
If you are afraid of any regressions, then just wait for the October packages as there is most likeley a fxed version included.
For SPS 2010, please see my fellows blog with all Info about the known issues and its resolutions here: blogs.technet.com/.../update-on-september-security-bulletin-ms11-074-and-sharepoint-2010-issues.aspx