What is CVE-2021-20263?

CVE-2021-20263 is a low-severity vulnerability in Qemu, classified under Improper Preservation of Permissions. CVSS score: 3.3/10. Published 2021-03-09.

How severe is CVE-2021-20263?

Low severity. CVSS v3 base score is 3.3 out of 10.

Vulnerability in Qemu

CVE-2021-20263

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.

EPSS: 0.004 (30.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.

Affected products

Qemu
N/a Qemu — versions qemu 5.2.50

Weakness classification (CWE)

CWE-281 — Improper Preservation of Permissions

References

secalert@redhat.com (Patch, Third Party Advisory, x_refsource_MISC, Issue Tracking)
secalert@redhat.com (Patch, Mailing List, Third Party Advisory, x_refsource_MISC)
secalert@redhat.com (x_refsource_CONFIRM, Third Party Advisory)
secalert@redhat.com (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)

Frequently asked questions

What is CVE-2021-20263?: CVE-2021-20263 is a low-severity vulnerability in Qemu, classified under Improper Preservation of Permissions. CVSS score: 3.3/10. Published 2021-03-09.
How severe is CVE-2021-20263?: Low severity. CVSS v3 base score is 3.3 out of 10.