CISA Adds Microsoft SharePoint Code Injection to KEV
Tech GuruQuick Answer
The authority published CISA KEV: CVE-2026-65660 for Microsoft SharePoint Server 2016, SharePoint Server 2019, and SharePoint Server Subscription Edition on x64 systems. CISA added the authorized-attacker code-injection vulnerability to KEV on September 25 and requires federal remediation by September 28. Microsoft's CNA record and August security-update pages identify the affected SharePoint product lines and fixed builds. Affected deployments should be matched to the authority's exact scope and moved to the supported fixed release.
Confirm Scope And Apply The Supported Fix
What to do now: Inventory Microsoft SharePoint Server 2016, SharePoint Server 2019, and SharePoint Server Subscription Edition on x64 systems, match the exact affected release or feature, apply the authority-supported fixed build or service remediation, validate the dependent workflow, and preserve evidence.
Last verified: 2026-09-26 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.
Scope And Authority
| Product scope | Microsoft SharePoint Server 2016, SharePoint Server 2019, and SharePoint Server Subscription Edition on x64 systems |
|---|---|
| Advisory | CISA KEV: CVE-2026-65660 |
| CVE | CVE-2026-65660 |
| Authoritative release date | 2026-09-25 14:39:25.365400 UTC |
| Authority revision date | 2026-09-25 15:41:24.086 UTC |
| Affected versions | SharePoint Server 2016 builds before 16.0.5565.1001, SharePoint Server 2019 builds before 16.0.10417.20198, and Subscription Edition builds before 16.0.19725.20522. |
| Fixed version | The applicable August 2026 Microsoft security update that reaches build 16.0.5565.1001, 16.0.10417.20198, or 16.0.19725.20522 |
| CVSS base score | 8.8 (official CVSS v3.1) |
| CVSS severity | High |
| Exploitation status | Known exploited: CISA added CVE-2026-65660 to KEV on 2026-09-25; known ransomware campaign use is Unknown; no exploitation claim is inferred. |
What Changed
CISA added the authorized-attacker code-injection vulnerability to KEV on September 25 and requires federal remediation by September 28. Microsoft's CNA record and August security-update pages identify the affected SharePoint product lines and fixed builds.
What To Validate Now
- Inventory. Locate Microsoft SharePoint Server 2016, SharePoint Server 2019, and SharePoint Server Subscription Edition on x64 systems deployments, versions, enabled features, exposure paths, owners, and dependent services.
- Establish applicability. Compare each deployment with the authority's affected-version statement: SharePoint Server 2016 builds before 16.0.5565.1001, SharePoint Server 2019 builds before 16.0.10417.20198, and Subscription Edition builds before 16.0.19725.20522. Do not infer applicability from product family or severity alone.
- Remediate. Apply The applicable August 2026 Microsoft security update that reaches build 16.0.5565.1001, 16.0.10417.20198, or 16.0.19725.20522 through the supported vendor or project channel, following the current advisory and change-control requirements.
- Validate. Confirm the resulting version or managed-service state, exercise representative functionality and recovery paths, monitor for regressions, and document exceptions.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
Use the exact supported release stream and repository. Test dependencies, clusters, integrations, and rollback before broad deployment; a CVSS rating or reachable feature is not evidence of exploitation.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
