CVE-2026-20952 Microsoft Office Remote Code Execution Vulnerability

High 8.4 Published Updated

An attacker can execute arbitrary code locally via a use-after-free flaw in Microsoft Office applications.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Local or same network only
Victim action needed
Not needed
Fix
None listed

What is CVE-2026-20952?

CVE-2026-20952 is a high-severity use after free vulnerability in Microsoft 365 Apps, published on 13 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.

Weakness: CWE-416

Which versions are affected by CVE-2026-20952?

It affects 3 products.

Products include Microsoft 365 Apps, Microsoft Office, Microsoft Office Long Term Servicing Channel.

How do I fix CVE-2026-20952?

No fix has been published for CVE-2026-20952 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2026-20952 being exploited?

There is no known exploitation of CVE-2026-20952 in the wild and no public exploit code.

All Microsoft 365 Apps vulnerabilities

Sources

Also known as GHSA-6pv3-4577-4j8m.

Is CVE-2026-20952 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free