CVE-2023-4623Use-after-free in Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component
Updated under an hour ago ()
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It affects Linux Kernel and 6 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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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.
- CVSS
- 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-416
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- NVD analysis
- Modified
- Record last updated
- Oct 14, 2026
- First seen by InfoSec Signals
- Oct 14, 2026
Affected products
Linux Kernel linux:kernel (from the name) | from 2.6.12 before 6.6 | CNA record |
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.0 before V3.1.5 | CISA ADP |
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name) | from V3.1.0 before V3.1.5 | CISA ADP |
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name) | before V1.1 | CISA ADP |
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.0 before V3.1.5 | CISA ADP |
linux linux_kernel linux:linux_kernel | from 2.6.12 before 4.14.327; from 4.15 before 4.19.295; from 4.20 before 5.4.257; from 5.5 before 5.10.195; from 5.11 before 5.15.132; from 5.16 before 6.1.53; from 6.2 before 6.4.16; from 6.5 before 6.5.3 | NVD |
debian debian_linux debian:debian_linux | 10.0 | NVD |
References
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b3d26c5702c7d6c45456326e56d2ccf3f103e60fpatch, issue-tracking, mailing-list, vendor-advisory
- https://kernel.dance/b3d26c5702c7d6c45456326e56d2ccf3f103e60fpatch, vendor-advisory
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.htmlmailing-list, third-party-advisory
- http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.htmlthird-party-advisory, vdb-entry
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlmailing-list, third-party-advisory
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
- https://cert-portal.siemens.com/productcert/html/ssa-769027.html
- https://cert-portal.siemens.com/productcert/html/ssa-794697.html
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.