CVE-2023-4207
A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.32%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.32% probability · 24th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- linux/linux kernel · debian/debian linux
- Source
- cve-coordination@google.com
References
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76e42ae831991c828cffa8c37736ebfb831ad5ecIssue Tracking, Mailing List, Patch, Vendor Advisory
- https://kernel.dance/76e42ae831991c828cffa8c37736ebfb831ad5ecPatch, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlMailing List, Third Party Advisory, VDB 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=76e42ae831991c828cffa8c37736ebfb831ad5ecIssue Tracking, Mailing List, Patch, Vendor Advisory
- https://kernel.dance/76e42ae831991c828cffa8c37736ebfb831ad5ecPatch, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlMailing List, Third Party Advisory, VDB Entry
- https://www.debian.org/security/2023/dsa-5492Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.