An update is available that improves management of weak certificate cryptographic algorithms in Windows

This update provides functionality that can be used to monitor the usage of weak cryptography and to block its use in enterprise environments. This update gives administrators logging capabilities and controls for the way that hashing algorithms and asymmetric cryptography are used in a managed environment. This functionality includes setting minimum key sizes for asymmetric algorithms such as RSA, DSA, and ECDSA, and blocking the use of weak hashing algorithms such as MD5.

After this update is applied, administrators can do the following: 

• Define policies to selectively block cryptographic algorithms that override settings that were provided by the operating system
• Opt-in to or opt-out of each policy independently
• Enable logging for each policy

For more information, go to the following Microsoft TechNet webpage:

Known issues with this security update

• Windows Update will not offer this security update to Windows RT-based computers until update 2808380 is installed. For more information, click the following article number to go to the article in the Microsoft Knowledge Base:
  2808380 Windows RT-based device cannot download software updates or Windows Store apps

Notice
On December 16, 2013, a detection change was made to correct an offering issue for Windows RT. The detection change helped to make sure that Windows Update correctly offers this security update (2835361) to Windows RT-based computers after update 2808380 is installed or after a later update rollup (that includes the 2808380 update) is installed. This was a detection change only. No changes were made to the update files. Customers who have successfully installed the update do not have to take any action.