Description
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation. When route4_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 b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.
CVSS breakdown
CVSS 3.1
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected products
- Linux / Kernel3.18 – 6.5
References
- MISChttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8
- MISChttps://kernel.dance/b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8
- VENDOR_ADVISORYhttps://www.debian.org/security/2023/dsa-5492
- MAILING_LISThttps://lists.debian.org/debian-lts-announce/2024/01/msg00004.html