Windows Server Netlogon Exploit Code Publicly Exposed, CISA Warns
The Cybersecurity and Infrastructure Security Agency (CISA) affirmed in a Monday announcement that code is publicly accessible that could be used to exploit a “Critical”-rated Netlogon vulnerability in newer Windows Server versions.
The vulnerability, known as CVE-2020-1472, could lead to elevation-of-privilege attacks if left unpatched. These Netlogon vulnerabilities are present in Windows Server 2019 and Windows Server 2016 products. A successful exploit could enable domain administrator privileges for an attacker, CISA’s announcement noted.
Last month, an exploit wasn’t publicly known, but it is now, according to Will Dormann, a vulnerability analyst at CERT/CC.
“Anybody who has not installed the patch from August’s [Microsoft’s] Patch Tuesday already is going to be in much worse shape than they already were,” Dormann indicated in a Twitter post.
Microsoft previously described a two-step approach to dealing with the Netlogon vulnerability. The first step involves installing a security patch that was released last month, which provides initial protection. The next step will be to turn on enforcement of secure Remote ProtoCol (RPC) for Netlogon, which will happen via a Feb. 9, 2021 patch. Organizations will need to have both patches in place. Otherwise, device users could experience access issues.
IT pros could have trouble locating vulnerable Netlogon clients in their organizations. Last month, Microsoft proposed using its Azure Sentinel cloud-based security information event management (SIEM) solution with its Insecure Protocols Workbook to find those vulnerabilities.
Kurt Mackie is senior news producer for 1105 Media’s Converge360 group.