CVE-2026-93834 HIGH

CVE-2026-93834: Qemu-kvm: 9pfs: use-after-free race in tlcreate/twalk allows vm guest escape

Vendor Red Hat
Product Red Hat Enterprise Linux 10
Weakness CWE-416
Published September 25, 2026
Last update September 25, 2026

CVSS base score

8.8/10
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

What the vulnerability does

01Description

A use-after-free vulnerability was found in QEMU's 9pfs subsystem. A race condition between the main thread and a worker thread when processing concurrent Tlcreate and Twalk requests allows a malicious guest user to craft a fid path containing stale heap data, bypassing directory traversal restrictions and escaping the shared directory boundary. This can lead to arbitrary host file read/write and code execution (VM escape) as the QEMU process user.

Key dates

02Disclosure timeline

September 25, 2026 CVE published
September 25, 2026 Record updated