CVE-2026-93834

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.0 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-93834
https://bugzilla.redhat.com/show_bug.cgi?id=2537939
https://gitlab.com/qemu-project/qemu/-/work_items/4491
https://gitlab.com/qemu-project/qemu/-/work_items/4491

Configurations

No configuration.

History

25 Sep 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-25 14:17

Updated : 2026-09-29 21:29

NVD link : CVE-2026-93834

Mitre link : CVE-2026-93834

CVE.ORG link : CVE-2026-93834

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

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