vulnerability
Red Hat: CVE-2023-4921: kernel: use-after-free in sch_qfq network scheduler (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:L/AC:L/Au:S/C:C/I:C/A:C) | Sep 12, 2023 | Feb 8, 2024 | Aug 11, 2025 |
Severity
7
CVSS
(AV:L/AC:L/Au:S/C:C/I:C/A:C)
Published
Sep 12, 2023
Added
Feb 8, 2024
Modified
Aug 11, 2025
Description
A 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.
Solutions
redhat-upgrade-kernelredhat-upgrade-kernel-rt
References
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