What is CVE-2026-49173?

CVE-2026-49173 is a high-severity vulnerability in Microsoft Windows 11 Version 26h1, classified under Use After Free. CVSS score: 7.8/10. Published 2026-07-14.

How severe is CVE-2026-49173?

High severity. CVSS v3 base score is 7.8 out of 10.

Use After Free in Microsoft Windows 11 Version 26h1

CVE-2026-49173

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

Vulnerability class: Use-After-Free

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft Windows 11 Version 26h1 — versions 10.0.28000.0

Weakness classification (CWE)

CWE-416 — Use After Free

References

secure@microsoft.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-49173?: CVE-2026-49173 is a high-severity vulnerability in Microsoft Windows 11 Version 26h1, classified under Use After Free. CVSS score: 7.8/10. Published 2026-07-14.
How severe is CVE-2026-49173?: High severity. CVSS v3 base score is 7.8 out of 10.