CVE-2023-4921

NameCVE-2023-4921
DescriptionA use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation. When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue(). We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
ReferencesDLA-3623-1, DLA-3710-1, ELA-1034-1, ELA-991-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
linux (PTS)jessie, jessie (lts)3.16.84-1vulnerable
stretch (security)4.9.320-2vulnerable
stretch (lts), stretch4.9.320-3vulnerable
buster4.19.249-2vulnerable
buster (security)4.19.304-1fixed
bullseye5.10.209-2fixed
bullseye (security)5.10.205-2fixed
bookworm6.1.76-1fixed
bookworm (security)6.1.85-1fixed
trixie6.6.15-2fixed
sid6.7.9-2fixed
linux-4.19 (PTS)jessie, jessie (lts)4.19.304-1~deb8u1fixed
stretch (security)4.19.232-1~deb9u1vulnerable
stretch (lts), stretch4.19.304-1~deb9u1fixed
linux-5.10 (PTS)jessie, jessie (lts)5.10.209-2~deb8u1fixed
stretch (lts), stretch5.10.209-2~deb9u1fixed
buster (security)5.10.209-2~deb10u1fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
linuxsourcejessie(unfixed)end-of-life
linuxsourcestretch(unfixed)end-of-life
linuxsourcebuster4.19.304-1DLA-3710-1
linuxsourcebullseye5.10.197-1
linuxsourcebookworm6.1.55-1
linuxsource(unstable)6.5.6-1
linux-4.19sourcejessie4.19.304-1~deb8u1ELA-1034-1
linux-4.19sourcestretch4.19.304-1~deb9u1ELA-1034-1
linux-5.10sourcejessie5.10.197-1~deb8u1ELA-991-1
linux-5.10sourcestretch5.10.197-1~deb9u1ELA-991-1
linux-5.10sourcebuster5.10.197-1~deb10u1DLA-3623-1

Notes

https://kernel.dance/#8fc134fee27f2263988ae38920bc03da416b03d8
https://git.kernel.org/linus/8fc134fee27f2263988ae38920bc03da416b03d8 (6.6-rc1)

Search for package or bug name: Reporting problems