Vulnerability 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 3.18, < 4.14.326 |
| Debian | Debian Linux | 12.0 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76Issue TrackingMailing ListPatch
- https://kernel.dance/76e42ae831991c828cffa8c37736ebfb831ad5ecPatchVendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlMailing ListThird Party AdvisoryVDB Entry
- https://www.debian.org/security/2023/dsa-5492Third Party Advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76Issue TrackingMailing ListPatch
- https://kernel.dance/76e42ae831991c828cffa8c37736ebfb831ad5ecPatchVendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlMailing ListThird Party AdvisoryVDB Entry
- https://www.debian.org/security/2023/dsa-5492Third Party Advisory
FAQ
What is CVE-2023-4207?
CVE-2023-4207 is a vulnerability with a CVSS score of 7.8 (HIGH). 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 tc...
How severe is CVE-2023-4207?
CVE-2023-4207 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-2023-4207?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel, Debian Debian Linux.