CVE-2026-93834

Publication date 29 September 2026

Last updated 30 September 2026


Ubuntu priority

Cvss 3 Severity Score

8.8 · High

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
qemu 26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
qemu-hwe 26.04 LTS resolute
Needs evaluation
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

Severity score breakdown

CVSS version: CVSS v3.0

Base score 8.8 · High

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


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