Use After Free Affecting kernel-rt package, versions <0:3.10.0-1160.105.1.rt56.1256.el7
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Test your applications- Snyk ID SNYK-CENTOS7-KERNELRT-5890416
- published 7 Sep 2023
- disclosed 29 Jul 2023
Introduced: 29 Jul 2023
CVE-2023-4208 Open this link in a new tabHow to fix?
Upgrade Centos:7 kernel-rt to version 0:3.10.0-1160.105.1.rt56.1256.el7 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kernel-rt package and not the kernel-rt package as distributed by Centos.
See How to fix? for Centos:7 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.
References
- https://access.redhat.com/security/cve/CVE-2023-4208
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81
- https://kernel.dance/3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81
- https://www.debian.org/security/2023/dsa-5492
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html