CVE-2026-45659: Microsoft SharePoint Remote Code Execution Vulnerability

In CISA’s Known Exploited Vulnerabilities catalog: Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability.

Added 2026-07-01, federal remediation due 2026-07-04. Known ransomware use: Known.

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. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.