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.
{
"cna_assigner": "Google",
"cwe_ids": [
"CWE-416"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/4xxx/CVE-2023-4208.json"
}{
"extracted_events": [
{
"introduced": "3.18"
},
{
"fixed": "6.5"
}
],
"source": "AFFECTED_FIELD"
}