CVE-2026-85879: CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition in Microsoft Windows Subsystem for Linux (WSL2)

This vulnerability is a TOCTOU race condition in Microsoft Windows Subsystem for Linux (WSL2) that can be exploited by an authorized local attacker to gain elevated privileges. The issue arises from a timing window between checking a condition and using the result, which can be manipulated to bypass security controls. The CVSS 3.1 base score is 7.0, indicating high severity, with attack vector local, high attack complexity, low privileges required, no user interaction, and impacts on confidentiality, integrity, and availability. Microsoft has published an official fix for this vulnerability.

An authorized local attacker can exploit this race condition to elevate their privileges, potentially gaining higher system rights than intended. This could lead to full system compromise, including unauthorized access to sensitive data and disruption of system operations.

Microsoft has released an official fix for this vulnerability. Users and administrators should apply the available security updates as soon as possible. No additional mitigation steps are indicated by the vendor advisory.