CVE-2026-59118 CRITICAL

CVE-2026-59118: Copilot Cowork Elevation of Privilege Vulnerability

Vendor Microsoft

Product Copilot Cowork

Weakness CWE-285

Published August 6, 2026

Last update August 21, 2026

View on NVD All CVEs

CVSS base score

9.3/10

Attack vector Network

Attack complexity Low

Privileges required None

User interaction Required

Confidentiality High

Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C

What the vulnerability does

01Description

Improper authorization in Copilot Cowork allows an unauthorized attacker to elevate privileges over a network.

Key dates

02Disclosure timeline

August 6, 2026 CVE published

August 21, 2026 Record updated

External resources

03References

NVD — National Vulnerability Database https://nvd.nist.gov/vuln/detail/CVE-2026-59118 CWE — Common Weakness Enumeration https://cwe.mitre.org/data/definitions/285.html AskarLabs — CWE-285 write-up Improper Authorization

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04Related CVE

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