Use After Free Affecting kernel-default-base package, versions <5.14.21-150400.24.92.1.150400.24.42.1


Severity

Recommended
0.0
high
0
10

Based on SUSE Linux Enterprise Server security rating.

Threat Intelligence

EPSS
0.04% (5th percentile)

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  • Snyk IDSNYK-SLES154-KERNELDEFAULTBASE-5965845
  • published14 Oct 2023
  • disclosed13 Oct 2023

Introduced: 13 Oct 2023

CVE-2023-4623  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade SLES:15.4 kernel-default-base to version 5.14.21-150400.24.92.1.150400.24.42.1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-default-base package and not the kernel-default-base package as distributed by SLES. See How to fix? for SLES:15.4 relevant fixed versions and status.

A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation.

If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free.

We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f.

CVSS Scores

version 3.1