CVE-2023-4623

Description

A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation. If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free. We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f.

References

https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html

https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html

https://kernel.dance/b3d26c5702c7d6c45456326e56d2ccf3f103e60f

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b3d26c5702c7d6c45456326e56d2ccf3f103e60f

http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3