What is CVE-2026-69617?

CVE-2026-69617 is a high-severity vulnerability in Microsoft Windows 11 Version 26h1, classified under Out-of-bounds Read. CVSS score: 7.0/10. Published 2026-09-08.

How severe is CVE-2026-69617?

High severity. CVSS v3 base score is 7.0 out of 10.

Out-of-bounds Read in Microsoft Windows 11 Version 26h1

CVE-2026-69617

Out-of-bounds read in Windows Resilient File System (ReFS) allows an authorized attacker to elevate privileges locally.

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft Windows 11 Version 26h1
Microsoft Windows Server 2025
Microsoft Windows Server 2025 (Server Core Installation)

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read

References

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

Frequently asked questions

What is CVE-2026-69617?: CVE-2026-69617 is a high-severity vulnerability in Microsoft Windows 11 Version 26h1, classified under Out-of-bounds Read. CVSS score: 7.0/10. Published 2026-09-08.
How severe is CVE-2026-69617?: High severity. CVSS v3 base score is 7.0 out of 10.