CVE-2021-20181

HIGH

QEMU <= 5.2.0 - Use-After-Free via 9pfs Server Race Condition

Title source: llm
STIX 2.1

Description

A race condition flaw was found in the 9pfs server implementation of QEMU up to and including 5.2.0. This flaw allows a malicious 9p client to cause a use-after-free error, potentially escalating their privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity as well as system availability.

References (5)

Core 5
Core References
Third Party Advisory, VDB Entry x_refsource_misc
https://www.zerodayinitiative.com/advisories/ZDI-21-159/
Mailing List, Third Party Advisory mailing-list x_refsource_mlist
https://lists.debian.org/debian-lts-announce/2021/02/msg00024.html
Issue Tracking, Patch, Third Party Advisory x_refsource_misc
https://bugzilla.redhat.com/show_bug.cgi?id=1927007
Third Party Advisory x_refsource_confirm
https://security.netapp.com/advisory/ntap-20210720-0009/
Mailing List, Third Party Advisory mailing-list x_refsource_mlist
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html

Scores

CVSS v3 7.5
EPSS 0.0006
EPSS Percentile 17.2%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

Details

CWE
CWE-367 CWE-362
Status published
Products (3)
debian/debian_linux 9.0
debian/debian_linux 10.0
qemu/qemu < 5.2.0
Published May 13, 2021
Tracked Since Feb 18, 2026