Wind River Support Network


LIN1021-6497 : Security Advisory - linux - CVE-2023-4208

Created: Sep 6, 2023    Updated: Sep 13, 2023
Resolved Date: Sep 7, 2023
Found In Version:
Severity: Standard
Applicable for: Wind River Linux LTS 21
Component/s: Kernel


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.

CREATE(Triage):(User=admin) CVE-2023-4208 (


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