CVE-2026-64901 Microsoft SharePoint Server Remote Code Execution Vulnerability

High 8.8 Published Updated

An authorized attacker can execute arbitrary code remotely via unsafe deserialization in Microsoft SharePoint Server.

Exploited in the wild
Not known
Login needed
Any signed-in user
Attackable
Over the internet
Victim action needed
Not needed
Fix
None listed

What is CVE-2026-64901?

CVE-2026-64901 is a high-severity unsafe deserialization vulnerability in Microsoft Sharepoint Server, published on 11 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

Weakness: CWE-502

Which versions are affected by CVE-2026-64901?

It affects 1 product.

Products include Microsoft Sharepoint Server.

How do I fix CVE-2026-64901?

No fix has been published for CVE-2026-64901 yet. Limit exposure of the affected software until one is available.

Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.

Is CVE-2026-64901 being exploited?

There is no known exploitation of CVE-2026-64901 in the wild and no public exploit code.

All Microsoft Sharepoint Server vulnerabilities

Sources

Also known as GHSA-8r25-8pqr-9xg6.

Is CVE-2026-64901 in your software?

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

Check your SBOMs for free