CVE-2026-65660
Microsoft SharePoint Code Injection Vulnerability
Microsoft SharePoint contains a code injection vulnerability which could allow an authorized attacker to execute code over a network.
CISA due Sep 28, 2026
- Microsoft SharePoint
- High
- CVSS 8.8
- EPSS 2.1%
- Fixed version listed
What to do
Fixed version listed
- Required action
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable.
- CISA deadline for US federal agencies
- Sep 28, 2026
Affected products
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Microsoft SharePoint Enterprise Server 2016 (x64-based Systems) | from 16.0.0, before 16.0.5565.1001 | 16.0.5565.1001 |
| Microsoft Microsoft SharePoint Server 2019 (x64-based Systems) | from 16.0.0, before 16.0.10417.20198 | 16.0.10417.20198 |
| Microsoft Microsoft SharePoint Server Subscription Edition (x64-based Systems) | from 16.0.0, before 16.0.19725.20522 | 16.0.19725.20522 |
Advisories and fixes
- Vendor advisory msrc.microsoft.com
Scores and signals
- Exploitation
- Exploited in the wild
- Severity
- High, CVSS 8.8 (v3.1, scored by microsoft)
- EPSS
- 2.1% chance of exploitation in the next 30 days (EPSS from FIRST, as of Oct 23, 2026)
- CISA's SSVC decision points
- Exploitation: active. Automatable: no. Technical impact: total. As of Sep 24, 2026.
- Weakness
- CWE-94: Improper Control of Generation of Code ('Code Injection')
- Vendor
- Microsoft, SharePoint
Timeline
- Added to CISA's Known Exploited Vulnerabilities catalog: exploited in the wild. US federal agencies must remediate by 2026-09-28.