Microsoft Mandates HTTPS for Organizations Using Windows Server Update Services
Microsoft announced on Tuesday that the installation of its September security updates could stop future software updates from arriving if organizations using its Windows Server Update Services (WSUS) solution for patch management are connecting using the HTTP protocol rather than HTTPS.
HTTPS adds Transport Layer Security encryption to client and Web server connections, which is considered to be a block against so-called "man-in-the-middle" attacks or tampering. Organizations shouldn't use HTTP to connect with Microsoft's content delivery network to get patches, Microsoft contends. And while organizations may have some internal servers using HTTP that don't connect to the Internet that are involved with delivering software updates to client devices, Microsoft is not thrilled with that approach either as it breaks the "chain of trust."
Microsoft is also leery about the use of client proxies to get patch content for internal servers that use HTTP. Organizations should use system proxies instead.
Client proxies are potentially subject to tampering, Microsoft argued.
"When using a user-based proxy, a user, even one without elevated privileges, could intercept and manipulate the data being exchanged between the update client and the update server," explained Aria Carley of Microsoft in the announcement.
In essence, the September security updates will trigger a crackdown on the use of HTTP with WSUS for future patching operations. IT pros will need to ensure that the following actions are taken before the next "update Tuesday" patch day (namely, Oct. 13) arrives, according to Microsoft:
- Secure your WSUS environment with TLS/SSL protocol (configure servers with HTTPS).
- Set up system-based proxy for detecting updates if needed.
- Enable the "Allow user proxy to be used as a fallback if detection using system proxy fails" policy.
The announcement warned that "if none of these actions are taken your devices will stop successfully scanning for software updates after the September 2020 security update."
No particular September patch was identified as being the one to trigger this new policy against HTTP use with WSUS. Last month, Microsoft had simply recommended the use of HTTPS with WSUS as a best practices security approach. Next month, though, HTTPS use with WSUS will be a requirement to continue to get security patches.
Kurt Mackie is senior news producer for 1105 Media's Converge360 group.