It appears that Microsoft has issued the fixed update:
https://technet.microsoft.com/en-us/security/bulletin/ms13-057
See the "Update FAQ" section:
"Why was this bulletin revised on August 13, 2013?
Microsoft revised this bulletin to rerelease the 2803821 update for Windows 7 and Windows Server 2008 R2.
The rereleased update addresses an application compatibility issue in which WMV encoded video could fail to properly render during playback. Windows 7 and Windows Server 2008 R2 customers should install the rereleased update."