CVE-2023-4623
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.
| Software | From | Fixed in |
|---|---|---|
| debian / debian_linux | 10.0 | 10.0.x |
| linux / linux_kernel | 4.15 | 4.19.295 |
| linux / linux_kernel | 6.5 | 6.5.3 |
| linux / linux_kernel | 6.2 | 6.4.16 |
| linux / linux_kernel | 5.16 | 6.1.53 |
| linux / linux_kernel | 5.11 | 5.15.132 |
| linux / linux_kernel | 5.5 | 5.10.195 |
| linux / linux_kernel | 4.20 | 5.4.257 |
| linux / linux_kernel | 2.6.12 | 4.14.327 |
- http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b3d26c5702c7d6c45456326e56d2ccf3f103e60f
- https://kernel.dance/b3d26c5702c7d6c45456326e56d2ccf3f103e60f
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html
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