CVE-2023-4208

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.

• CVE ID
• CVE-2023-4208

• Assigner
• Google

• Vulnerability Status
• PUBLISHED

• Published Version
• 2023-09-06T13:53:23.843Z

• Last Modified Date
• 2023-09-06T13:53:23.843Z