Use After Free Affecting kernel package, versions <0:4.18.0-305.120.1.el8_4


Severity

Recommended
0.0
high
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.05% (19th percentile)

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  • Snyk IDSNYK-RHEL8-KERNEL-6217277
  • published31 Jan 2024
  • disclosed5 Sept 2023

Introduced: 5 Sep 2023

CVE-2023-4921  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade RHEL:8 kernel to version 0:4.18.0-305.120.1.el8_4 or higher.
This issue was patched in RHSA-2024:0562.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel package and not the kernel package as distributed by RHEL. See How to fix? for RHEL:8 relevant fixed versions and status.

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.

CVSS Scores

version 3.1