What is GHSA-mfc9-f34v-g35g?

GHSA-mfc9-f34v-g35g is a security advisory published by GitHub Security Advisories with High severity. Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.

Which CVE IDs does GHSA-mfc9-f34v-g35g cover?

GHSA-mfc9-f34v-g35g covers the following CVE IDs: CVE-2026-83866. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-mfc9-f34v-g35g?

GHSA-mfc9-f34v-g35g has a CVSS v3 base score of 7.0, published by GitHub Security Advisories.

GHSA-mfc9-f34v-g35gHighCVSS 7.0

Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.

Vendor

GitHub Security Advisories

Published

October 13, 2026

Last Modified

October 13, 2026

🔗 CVE IDs covered (1)

CVE-2026-83866 →

📋 Description

Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.

🔗 References (3)

https://nvd.nist.gov/vuln/detail/CVE-2026-83866
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83866
https://github.com/advisories/GHSA-mfc9-f34v-g35g