CVE-2026-56164 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-56164CRITICAL

Microsoft SharePoint Server Elevation of Privilege Vulnerability

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  H  H  H    9.8   .2244   97.5   YES

AFFECTED
  Product                                           Versions  Fixed
  Microsoft SharePoint Enterprise Server 2016       16.0.0 –  —
  Microsoft SharePoint Server 2019                  16.0.0 –  —
  Microsoft SharePoint Server Subscription Edition  16.0.0 –  —

TIMELINE
  Jun 19  Reserved by microsoft
  Jul 14  Added to CISA KEV, remediation due 2026-07-17
  Jul 14  Published (CNA: microsoft)
  Jul 18  DUE DATE PASSED — CVE-2026-56164 (Microsoft SharePoint Enterprise Server 2016). CISA remediation deadline was July 17, 2026; still in catalog.

CWE-306 · CNA: microsoft · CVSS v3.1 · 2 references · NVD status: Analyzed · KEV due July 17, 2026

Description

Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
June 19, 2026	Reserved	Reserved by microsoft
July 14, 2026	KEV ADDED	Added to CISA KEV, remediation due 2026-07-17
July 14, 2026	Published	Published (CNA: microsoft)
July 18, 2026	DUE DATE PASSED	DUE DATE PASSED — CVE-2026-56164 (Microsoft SharePoint Enterprise Server 2016). CISA remediation deadline was July 17, 2026; still in catalog.

Affected

Affected products and packages — 3 rows
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
Microsoft	Microsoft SharePoint Enterprise Server 2016	—	16.0.0	—
Microsoft	Microsoft SharePoint Server 2019	—	16.0.0	—
Microsoft	Microsoft SharePoint Server Subscription Edition	—	16.0.0	—

Weaknesses

CWE-306

References (2)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164 [vendor-advisory, patch]
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56164 [government-resource]

Authoritative record: CVE-2026-56164 at cve.org

Vendors: microsoft

Weaknesses: CWE-306

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-56164 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.