Use After Free Affecting kernel-rt-debug-modules-extra package, versions <0:4.18.0-513.5.1.rt7.307.el8_9


Severity

Recommended
0.0
high
0
10

Based on CentOS security rating.

Threat Intelligence

EPSS
0.04% (5th percentile)

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  • Snyk IDSNYK-CENTOS8-KERNELRTDEBUGMODULESEXTRA-5890079
  • published7 Sept 2023
  • disclosed29 Jul 2023

Introduced: 29 Jul 2023

CVE-2023-4208  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Centos:8 kernel-rt-debug-modules-extra to version 0:4.18.0-513.5.1.rt7.307.el8_9 or higher.

NVD Description

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

A use-after-free vulnerability in the Linux kernel's net/sched: cls_u32 component can be exploited to achieve local privilege escalation.

When u32_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.

We recommend upgrading past commit 3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81.

CVSS Scores

version 3.1