CVE-2021-20263
First published: Mon Mar 01 2021(Updated: )
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.
Credit: secalert@redhat.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| redhat/qemu | <5.2.50 | 5.2.50 |
| QEMU qemu | >=5.0.0<5.2.50 |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
- https://gitlab.com/virtio-fs/qemu/-/commit/6084633dff3a05d6317
- https://git.qemu.org/?p=qemu.git;a=commit;h=e586edcb410543768ef009eaa22a2d9dd4a53846
- https://lists.gnu.org/archive/html/qemu-devel/2021-03/msg01244.html
- https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=1935089
- https://www.openwall.com/lists/oss-security/2021/03/08/1
- https://bugzilla.redhat.com/show_bug.cgi?id=1933668
- https://security.gentoo.org/glsa/202208-27
- https://security.netapp.com/advisory/ntap-20210507-0002/
Frequently Asked Questions
What is CVE-2021-20263?
CVE-2021-20263 is a vulnerability found in the virtio-fs shared file system daemon (virtiofsd) of QEMU.
What is the impact of CVE-2021-20263?
The vulnerability may allow an attacker to create a modified, privileged executable in the guest system.
How can I fix CVE-2021-20263?
Update the QEMU package to version 5.2.50 or apply the provided remedy.
What is the severity level of CVE-2021-20263?
The severity level of CVE-2021-20263 is low, with a CVSS score of 3.3.
What is the Common Weakness Enumeration (CWE) of CVE-2021-20263?
The CWE of CVE-2021-20263 is CWE-281.
- collector/nvd-index
- agent/references
- agent/type
- agent/remedy
- agent/softwarecombine
- agent/first-publish-date
- collector/mitre-cve
- source/MITRE
- agent/last-modified-date
- agent/weakness
- agent/author
- agent/severity
- agent/description
- agent/tags
- agent/event
- collector/redhat-bugzilla
- source/Red Hat
- alias/CVE-2021-20263
- agent/software-canonical-lookup
- vendor/qemu
- canonical/qemu qemu
- version/qemu qemu/5.0.0
- package-manager/redhat