Microsoft SharePoint Code Injection Vulnerability (CVE-2026-65660) is being actively exploited, CISA warns
CISA added CVE-2026-65660 (Microsoft SharePoint) to its Known Exploited Vulnerabilities catalog on September 25, 2026, which means there is reliable evidence of exploitation in the wild. Microsoft SharePoint contains a code injection vulnerability which could allow an authorized attacker to execute code over a network.
Excerpt from the primary source: CISA Known Exploited Vulnerabilities
Who is affected
Enterprises
Affected technology: SharePoint
Why it matters
CISA lists this as exploited in the wild. Unpatched SharePoint systems are exposed to active attacks now.
Automated: stated only from CISA listings and the exploitation evidence in the sources below.
What you should do · Patch
Apply the vendor's security update for SharePoint. Check the linked advisory for affected and fixed versions, and put internet-facing systems first.
CISA's required action for CVE-2026-65660: "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. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines." US federal civilian agencies must comply by September 28, 2026.
Automated guidance based on this story's classification. Check the linked advisories for specifics.
Sources
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CISA Adds Two Known Exploited Vulnerabilities to Catalog
CISA has added two new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog , based on evidence of active exploitation. CVE-2026-65660 Microsoft SharePoint Code Injection Vulnerability CVE-2026-67279 Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Vulnerability These types of vulnerabilities are a frequent attack vector for malicious cyber actors and pose significant risks to the…
CISA lists this as exploited in the wild. Unpatched SharePoint and RouterOS systems are exposed to active attacks now.
Apply the vendor's security update for SharePoint and RouterOS.