---
id: CVE-2023-23454
title: >-
  cbq_classify in net/sched/sch_cbq.c in the Linux kernel through 6.1.4 allows
  attackers to cause a denial of service (slab-out-of-bounds read) because of
  type confusion (non-negative numbers can sometimes indicate a TC_ACT_SHOT
  condition …
summary: >-
  cbq_classify in net/sched/sch_cbq.c in the Linux kernel through 6.1.4 allows
  attackers to cause a denial of service (slab-out-of-bounds read) because of
  type confusion (non-negative numbers can sometimes indicate a TC_ACT_SHOT
  condition …
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-843
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.12, <= 6.1.4'
  - debian_linux = 11.0
published: '2023-01-12'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T23:17:12.283'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-23454'
references:
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=caa4b35b4317d5147b3ab0fbdc9c075c7d2e9c12
    label: cve@mitre.org
  - url: 'https://lists.debian.org/debian-lts-announce/2023/03/msg00000.html'
    label: cve@mitre.org
  - url: 'https://lists.debian.org/debian-lts-announce/2023/05/msg00006.html'
    label: cve@mitre.org
  - url: 'https://www.debian.org/security/2023/dsa-5324'
    label: cve@mitre.org
  - url: 'https://www.openwall.com/lists/oss-security/2023/01/10/1'
    label: cve@mitre.org
  - url: 'https://www.openwall.com/lists/oss-security/2023/01/10/4'
    label: cve@mitre.org
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=caa4b35b4317d5147b3ab0fbdc9c075c7d2e9c12
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2023/03/msg00000.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2023/05/msg00006.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.debian.org/security/2023/dsa-5324'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.openwall.com/lists/oss-security/2023/01/10/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.openwall.com/lists/oss-security/2023/01/10/4'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-769027.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-794697.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-806742.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00312
epssPercentile: 0.22422
ingestedAt: '2026-10-15T00:02:07.124Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2025-03-06T15:57:34.523485Z'
---

## Overview

cbq_classify in net/sched/sch_cbq.c in the Linux kernel through 6.1.4 allows attackers to cause a denial of service (slab-out-of-bounds read) because of type confusion (non-negative numbers can sometimes indicate a TC_ACT_SHOT condition rather than valid classification results).

## Affected

- `linux_kernel >= 2.6.12, <= 6.1.4`
- `debian_linux = 11.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.