An automatic updater of untrusted certificates is available for Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2. This updater expands on the existing automatic root update mechanism technology that is found in Windows Vista and in Windows 7 to let certificates that are compromised or are untrusted in some way be specifically flagged as untrusted.
A certificate trust list (CTL) is a predefined list of items that are signed by a trusted entity. All the items in the list are authenticated and approved by a trusted signing entity. This update expands on this existing functionality by adding known untrusted certificates to the untrusted certificate store by using a CTL that contains either their public key or their signature hash. After this update is installed, customers benefit from quick automatic updates of untrusted certificates.
Users who have disconnected systems will not benefit from this feature improvement. These customers will still have to install the root certificate updates when they are made available. Please see the "More Information" section.
As part of this update, the URLs that are used for contacting Windows Update to download the untrusted and trusted CTLs were changed. This could cause problems for enterprises that hardcode these URLs in their firewalls as exceptions.
The following are the new URLs:
A certificate trust list (CTL) is a predefined list of items that are signed by a trusted entity. All the items in the list are authenticated and approved by a trusted signing entity. This update expands on this existing functionality by adding known untrusted certificates to the untrusted certificate store by using a CTL that contains either their public key or their signature hash. After this update is installed, customers benefit from quick automatic updates of untrusted certificates.
Users who have disconnected systems will not benefit from this feature improvement. These customers will still have to install the root certificate updates when they are made available. Please see the "More Information" section.
As part of this update, the URLs that are used for contacting Windows Update to download the untrusted and trusted CTLs were changed. This could cause problems for enterprises that hardcode these URLs in their firewalls as exceptions.
The following are the new URLs:
http://ctldl.windowsupdate.com/msdownload/update/v3/static/trustedr/en/disallowedcertstl.cab
http://ctldl.windowsupdate.com/msdownload/update/v3/static/trustedr/en/authrootstl.cab
http://ctldl.windowsupdate.com/msdownload/update/v3/static/trustedr/en/authrootstl.cab