CVE-2023-4208: exploitation status and patch state
CVE-2023-4208 · CVSS 7.8 HIGH · EPSS <1%
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.
Is CVE-2023-4208 exploited?
Not in the CISA KEV catalog.
EPSS puts exploitation in the next 30 days at <1%.
Public exploit code: none found in monitored sources.