CISA Adds Microsoft SharePoint Vulnerability to KEV Catalog

CISA ICS-CERT Advisories

Published March 18th, 2026

Detected March 19th, 2026

Summary

CISA has added CVE-2026-20963, a Microsoft SharePoint deserialization vulnerability, to its Known Exploited Vulnerabilities (KEV) Catalog due to evidence of active exploitation. Federal Civilian Executive Branch (FCEB) agencies are required to remediate this vulnerability.

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What changed

CISA has added CVE-2026-20963, a Microsoft SharePoint Deserialization of Untrusted Data vulnerability, to its Known Exploited Vulnerabilities (KEV) Catalog. This action is based on evidence of active exploitation and highlights the significant risk such vulnerabilities pose to federal networks. The addition to the KEV Catalog triggers Binding Operational Directive (BOD) 22-01 requirements for Federal Civilian Executive Branch (FCEB) agencies.

FCEB agencies must remediate CVE-2026-20963 by the due date specified in BOD 22-01 to protect their networks. While BOD 22-01 specifically applies to FCEB agencies, CISA strongly urges all organizations to prioritize the remediation of vulnerabilities listed in the KEV Catalog as part of their ongoing vulnerability management practices to mitigate cyberattack risks.

What to do next

FCEB agencies must remediate CVE-2026-20963 by the deadline specified in BOD 22-01.
All organizations are strongly urged to prioritize remediation of CVE-2026-20963 as part of their vulnerability management.

Penalties

BOD 22-01 requires FCEB agencies to remediate identified vulnerabilities by the due date.

Source document (simplified)

Alert

CISA Adds One Known Exploited Vulnerability to Catalog

Release Date

March 18, 2026

CISA has added one new vulnerability to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation.

CVE-2026-20963 Microsoft SharePoint Deserialization of Untrusted Data Vulnerability This type of vulnerability is a frequent attack vector for malicious cyber actors and poses significant risks to the federal enterprise.

Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and Exposures (CVEs) that carry significant risk to the federal enterprise. BOD 22-01 requires Federal Civilian Executive Branch (FCEB) agencies to remediate identified vulnerabilities by the due date to protect FCEB networks against active threats. See the BOD 22-01 Fact Sheet for more information.

Although BOD 22-01 only applies to FCEB agencies, CISA strongly urges all organizations to reduce their exposure to cyberattacks by prioritizing timely remediation of KEV Catalog vulnerabilities as part of their vulnerability management practice. CISA will continue to add vulnerabilities to the catalog that meet the specified criteria.

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