CVE-2026-85879: Windows Subsystem for Linux Elevation of Privilege Vulnerability

Overview

Severity

High (CVSS 7)

CVSS Vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Elevation of Privilege

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Oct

Released

2026-10-13

Description

Time-of-check time-of-use (toctou) race condition in Windows Subsystem for Linux allows an authorized attacker to elevate privileges locally.

FAQ

What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain SYSTEM privileges. According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability? Successful exploitation of this vulnerability requires an attacker to win a race condition.

Affected Products (1)

Open Source Software

• Windows Subsystem for Linux (WSL2)

Security Updates (1)

• Release Notes

Acknowledgments

vurmusum, vurmusum, <a href="https://www.linkedin.com/in/gikaku/">HE WEI（ギカク）</a>

Revision History

• 2026-10-13: Information published.