Buffer overflow in Microsoft Windows 10 Version 21h2

CVE-2026-69820

Heap-based buffer overflow in Windows Hello allows an authorized attacker to elevate privileges locally.

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-69820?
CVE-2026-69820 is a high-severity vulnerability in Microsoft Windows 10 Version 21h2, classified under Heap-based Buffer Overflow. CVSS score: 8.2/10. Published 2026-09-08.
How severe is CVE-2026-69820?
High severity. CVSS v3 base score is 8.2 out of 10.