vulnerability

Alma Linux: CVE-2023-4623: Important: kernel security update (ALSA-2024-0897)

Severity
7
CVSS
(AV:L/AC:L/Au:S/C:C/I:C/A:C)
Published
Sep 6, 2023
Added
Feb 23, 2024
Modified
Aug 11, 2025

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.

Solutions

alma-upgrade-bpftoolalma-upgrade-kernelalma-upgrade-kernel-abi-stablelistsalma-upgrade-kernel-corealma-upgrade-kernel-cross-headersalma-upgrade-kernel-debugalma-upgrade-kernel-debug-corealma-upgrade-kernel-debug-develalma-upgrade-kernel-debug-modulesalma-upgrade-kernel-debug-modules-extraalma-upgrade-kernel-develalma-upgrade-kernel-docalma-upgrade-kernel-modulesalma-upgrade-kernel-modules-extraalma-upgrade-kernel-toolsalma-upgrade-kernel-tools-libsalma-upgrade-kernel-tools-libs-develalma-upgrade-kernel-zfcpdumpalma-upgrade-kernel-zfcpdump-corealma-upgrade-kernel-zfcpdump-develalma-upgrade-kernel-zfcpdump-modulesalma-upgrade-kernel-zfcpdump-modules-extraalma-upgrade-perfalma-upgrade-python3-perf
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