Paul Stone and Alex Chapman of Context Information Security in the U.K. took a long look at the WSUS attack surface and discovered that when a WSUS server contacts Microsoft for driver updates, it does so using XML SOAP web services, and those checks are not made over SSL. While updates are signed by Microsoft and updates must be verified by Microsoft, Stone and Chapman discovered that an attacker already in a man-in-the-middle position on a corporate network, for example, could with some work tamper with the unencrypted communication and inject a malicious homegrown update.

Source: Manipulating Microsoft WSUS to Own Enterprises | Threatpost | The first stop for security news