CVE-2026-65665Critical
Microsoft SharePoint Server Remote Code Execution Vulnerability
Assessment
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
- Severity
- Critical
- CVSS base score
- 8.8CVSS:3.1/
AV:N/ AC:L/ PR:L/ UI:N/ S:U/ C:H/ I:H/ A:H/ E:U/ RL:O/ RC:C - Impact
- Remote Code Execution
- EPSS, next 30 days
- 1.7%Higher than 76.2% of scored CVEs · FIRST model run 26 Sep 2026 · about EPSS
- Exploitability
- Exploitation More Likely
- Publicly disclosed
- No
- Customer action
- Required: apply the update
- Component
- Microsoft Office SharePoint
- Weakness
- CWE-502: Deserialization of Untrusted Data
- Issued by
- Microsoft
- Published
- 11 Aug 2026 · August 2026
- Last revised
- 11 Aug 2026
Updates that fix it
3 KBs| KB | Type | Restart | Applies to | Other CVEs |
|---|---|---|---|---|
| KB5002893 | Security Update | — | Microsoft SharePoint Server Subscription Edition | All CVEs in KB5002893 |
| KB5002894 | Security Update | — | Microsoft SharePoint Server 2019 | All CVEs in KB5002894 |
| KB5002896 | Security Update | — | Microsoft SharePoint Server 2019 | All CVEs in KB5002896 |
Affected products
Microsoft Office2 affected products
- Microsoft SharePoint Server 2019
- Microsoft SharePoint Server Subscription Edition