| Name | CVE-2021-20263 |
| 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 985083 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| qemu (PTS) | buster | 1:3.1+dfsg-8+deb10u8 | fixed |
| buster (security) | 1:3.1+dfsg-8+deb10u12 | fixed | |
| bullseye | 1:5.2+dfsg-11+deb11u3 | fixed | |
| bullseye (security) | 1:5.2+dfsg-11+deb11u2 | fixed | |
| bookworm | 1:7.2+dfsg-7+deb12u5 | fixed | |
| trixie | 1:8.2.1+ds-2 | fixed | |
| sid | 1:8.2.2+ds-2 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| qemu | source | stretch | (not affected) | |||
| qemu | source | buster | (not affected) | |||
| qemu | source | (unstable) | 1:5.2+dfsg-9 | 985083 |
[buster] - qemu <not-affected> (Introduced in 5.2.0)
[stretch] - qemu <not-affected> (Introduced in 5.2.0)
https://bugzilla.redhat.com/show_bug.cgi?id=1933668
Introduced in: https://git.qemu.org/?p=qemu.git;a=commit;h=725ca3313a5b9cbef89eaa1c728567684f37990a
Fixed by: https://git.qemu.org/?p=qemu.git;a=commit;h=e586edcb410543768ef009eaa22a2d9dd4a53846
https://git.qemu.org/?p=qemu.git;a=commit;h=e586edcb410543768ef009eaa22a2d9dd4a53846
https://git.qemu.org/?p=qemu.git;a=commit;h=1e08f164e9fdc9528ad6990012301b9a04b0bc90