Vulnerability Description
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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 3.18, < 4.14.322 |
| Debian | Debian Linux | 12.0 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=30Vendor Advisory
- https://kernel.dance/3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlThird Party Advisory
- https://www.debian.org/security/2023/dsa-5492Third Party Advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=30Vendor Advisory
- https://kernel.dance/3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlThird Party Advisory
- https://www.debian.org/security/2023/dsa-5492Third Party Advisory
FAQ
What is CVE-2023-4208?
CVE-2023-4208 is a vulnerability with a CVSS score of 7.8 (HIGH). 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 ...
How severe is CVE-2023-4208?
CVE-2023-4208 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2023-4208?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel, Debian Debian Linux.