What’s Vulnerable › Vulnerabilities

CVE-2026-70321: Microsoft SharePoint Remote Code Execution Vulnerability

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-11 · updated 2026-10-30
• Weakness: CWE-502

Description

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

Affected products

• Microsoft SharePoint Server: before 16.0.19725.20522 — fixed in 16.0.19725.20522
• Microsoft SharePoint Server Subscription Edition: from 16.0.0 before 16.0.19725.20522 — fixed in 16.0.19725.20522

How to fix

Upgrade to a fixed version: Microsoft SharePoint Server 16.0.19725.20522; Microsoft SharePoint Server Subscription Edition 16.0.19725.20522. Check the vendor advisory for mitigations.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70321

Get alerted when CVE-2026-70321 or the next vulnerability affects your stack