CVE-2021-20263

LOW

QEMU virtio-fs - Privilege Escalation

Title source: llm
STIX 2.1

Description

A flaw was found in the virtio-fs shared file system daemon (virtiofsd) of QEMU. The new 'xattrmap' option may cause the 'security.capability' xattr in the guest to not drop on file write, potentially leading to a modified, privileged executable in the guest. In rare circumstances, this flaw could be used by a malicious user to elevate their privileges within the guest.

References (4)

Core 4
Core References
Issue Tracking, Patch, Third Party Advisory x_refsource_misc
https://bugzilla.redhat.com/show_bug.cgi?id=1933668
Mailing List, Patch, Third Party Advisory x_refsource_misc
https://www.openwall.com/lists/oss-security/2021/03/08/1
Third Party Advisory x_refsource_confirm
https://security.netapp.com/advisory/ntap-20210507-0002/
Third Party Advisory vendor-advisory x_refsource_gentoo
https://security.gentoo.org/glsa/202208-27

Scores

CVSS v3 3.3
EPSS 0.0038
EPSS Percentile 29.2%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Details

CWE
CWE-281
Status published
Products (1)
qemu/qemu 5.0.0 - 5.2.50
Published Mar 09, 2021
Tracked Since Feb 18, 2026