Use After Free Affecting kernel-tools package, versions <0:4.14.322-170.535.amzn1


Severity

Recommended
0.0
high
0
10

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.04% (6th percentile)

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  • Snyk IDSNYK-AMZN201803-KERNELTOOLS-5929116
  • published4 Oct 2023
  • disclosed6 Sept 2023

Introduced: 6 Sep 2023

CVE-2023-4206  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2018.03 kernel-tools to version 0:4.14.322-170.535.amzn1 or higher.
This issue was patched in ALAS-2023-1827.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-tools package and not the kernel-tools package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2018.03 relevant fixed versions and status.

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

When route4_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 b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.

CVSS Scores

version 3.1