Executive brief
A security vulnerability exists in the Windows Routing and Remote Access Service (RRAS), a component used to provide routing and VPN services. An attacker who already has basic access to a computer could exploit this flaw to gain full administrative control over the system. This could lead to unauthorized data access, installation of malicious software, or complete disruption of the affected server or workstation.
Technical details
An improper access control vulnerability (CWE-284) exists in the Windows Routing and Remote Access Service (RRAS). The flaw allows a locally authenticated attacker with low privileges to bypass security restrictions and elevate their privileges to a higher level, potentially SYSTEM. The attack vector is local, requiring the attacker to have existing execution capabilities on the target host. Microsoft has released security updates to address this issue across multiple versions of Windows and Windows Server.
Affected products
- Microsoft Windows 10 1607, 1809, 21H2, 22H2
- Microsoft Windows 11 22H3, 23H2, 24H2, 25H2
- Microsoft Windows Server 2008 R2 Service Pack 1
Timeline
- 2026-01-13: disclosed
- 2026-01-13: advisory