CVE-2023-4207

Description

A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. When fw_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 76e42ae831991c828cffa8c37736ebfb831ad5ec.

Weakness classification

• cve-coordination@google.com: CWE-416
• nvd@nist.gov: CWE-416

Primary references

• cve-coordination@google.com — Issue Tracking, Mailing List, Patch, Vendor Advisory
• cve-coordination@google.com — Patch, Vendor Advisory
• cve-coordination@google.com — Mailing List, Third Party Advisory, VDB Entry
• cve-coordination@google.com — Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Mailing List, Patch, Vendor Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Patch, Vendor Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Third Party Advisory, VDB Entry
• af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory