Time-of-check Time-of-use (TOCTOU) Race Condition in Microsoft Windows and Windows Server - CVE-2026-102200

Vulnerability identifier: #VU164610

CSH Severity: Low

CVSS v4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-102200

CWE-ID: CWE-367

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to tamper with data locally.

The vulnerability exists due to a time-of-check time-of-use race condition in Windows NTFS when a resource is checked and subsequently used. A local user can win the race by changing resource state between the check and its use to tamper with data.

Microsoft Windows
Windows Server

Install security update from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7846, 10 22H2 10.0.19045.7846, 10 1809 10.0.17763.9487, 11 23H2 10.0.22631.7711, 11 24H2 10.0.26100.9911, 11 24H2 10.0.26100.9974, 11 25H2 10.0.26200.9911, 11 25H2 10.0.26200.9974, 11 26H1 10.0.28000.3501
Windows Server - addressed in versions 2019 10.0.17763.9487, 2022 10.0.20348.5870, 2025 10.0.26100.33730, 2025 10.0.26100.33822

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-102200
• https://support.microsoft.com/help/5131085