Quick answers
- Is CVE-2026-20875 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-20875 being exploited in the wild.
- How severe is CVE-2026-20875?
- High severity, with a CVSS score of 7.5, published 13 January 2026.
- Which products and versions are affected?
- Microsoft Windows 11 22H3, 23H2, 24H2, 25H2; Microsoft Windows Server 2008 R2 Service Pack 1; Microsoft Windows 10 1607, 1809, 21H2, 22H2.
- Is there a fix for CVE-2026-20875?
- A patch was published on 2026-01-13. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-20875 attacked?
- It is attacked over the network, in an operating system.
- Am I affected by CVE-2026-20875?
- Check whether you run Microsoft Windows 11, Microsoft Windows Server 2008 R2 or Microsoft Windows 10 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A NULL pointer dereference vulnerability (CWE-476) exists within the Windows Local Security Authority Subsystem Service (LSASS). The flaw can be triggered by an unauthenticated attacker over the network without any user interaction. Successful exploitation causes the LSASS process to crash, which in turn triggers an immediate system reboot, resulting in a denial-of-service (DoS) condition. Microsoft has released security updates to address this issue across various versions of Windows 10, Windows 11, 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: patched