Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-80098

CVE-2026-80098CRITICAL

Microsoft Microsoft Copilot Studio — Copilot Studio Elevation of Privilege Vulnerability

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  C  H  H  H   10.0   .0049   39.8     —

AFFECTED
  Product                   Versions  Fixed
  Microsoft Copilot Studio  - –       —

TIMELINE
  Aug 25  Reserved by microsoft
  Sep 3   Published (CNA: microsoft)
  Sep 8   RESCORED — CVE-2026-80098 (Microsoft Copilot Studio). CVSS 9.3 → 10 (NVD).

CWE-347 · CNA: microsoft · CVSS v3.1 · 1 reference · NVD status: Analyzed

Description

Improper verification of cryptographic signature in Copilot Studio allows an unauthorized attacker to elevate privileges over a network.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
August 25, 2026	Reserved	Reserved by microsoft
September 3, 2026	Published	Published (CNA: microsoft)
September 8, 2026	RESCORED	RESCORED — CVE-2026-80098 (Microsoft Copilot Studio). CVSS 9.3 → 10 (NVD).

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
Microsoft	Microsoft Copilot Studio	—	-	—

Weaknesses

CWE-347

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80098 [vendor-advisory, patch]

Authoritative record: CVE-2026-80098 at cve.org

Vendors: microsoft

Weaknesses: CWE-347

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-80098 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 Sunday, October 4, 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.