Heap-based buffer overflow in Microsoft Windows - CVE-2026-69820
Published: September 8, 2026
Vulnerability identifier: #VU147975
CSH Severity: Low
CVSS v4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-69820
CWE-ID: CWE-122
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local privileged user to elevate privileges.
The vulnerability exists due to a heap-based buffer overflow in Windows Hello when exploited locally. A local privileged user can exploit the heap-based buffer overflow to elevate privileges.
Successful exploitation could provide Virtual Trust Level 1 (VTL1) privileges.
Affected software
Microsoft Windows
How to mitigate CVE-2026-69820
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7725, 10 22H2 10.0.19045.7725, 11 23H2 10.0.22631.7582, 11 24H2 10.0.26100.9445, 11 25H2 10.0.26200.9445, 11 26H1 10.0.28000.2954