CVE-2023-4623
Use-after-free in Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component
HIGH 7.8EPSS 0.3%
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.
- Affected
- Linux · Kernel
- CVSS v3.1 NVD
- 7.8 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.28% chance of exploitation in the next 30 days, 20th percentile
- Published
- 2023-09-06
- Updated
- 2026-10-14
Exploit collections (2)
- linux/kernelctf/CVE-2023-4623_lts_cosgoogle/security-research
- linux/kernelctf/CVE-2023-4623_mitigationgoogle/security-research
Security advisories
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b3d26c5702c…
- https://kernel.dance/b3d26c5702c7d6c45456326e56d2ccf3f103e60f
- http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1…
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html