---
id: CVE-2023-42754
title: A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack
summary: >-
  A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The
  socket buffer (skb) was assumed to be associated with a device before calling
  __ip_options_compile, which is not always the case if the skb is re-routed by
  ipv…
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-476
vendor: linux
product: linux_kernel
affected:
  - linux_kernel < 6.6
  - linux_kernel = 6.6
  - enterprise_linux = 8.0
  - enterprise_linux = 9.0
  - fedora = 37
  - fedora = 38
  - fedora = 39
patched:
  - linux_kernel 6.6
published: '2023-10-05'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T00:16:37.403'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-42754'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2024:2394'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:2950'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:3138'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2023-42754'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2239845'
    label: secalert@redhat.com
  - url: 'https://seclists.org/oss-sec/2023/q4/14'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:2394'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:2950'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:3138'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/security/cve/CVE-2023-42754'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2239845'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GISYSL3F6WIEVGHJGLC2MFNTUXHPTKQH/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GPMICQ2HVZO5UAM5KPXHAZKA2U3ZDOO6/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/V5PDNWPKAP3WL5RQZ4RIDS6MG32OHH5R/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://seclists.org/oss-sec/2023/q4/14'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-398330.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - 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
tags:
  - nvd
  - cve.org
epss: 0.00404
epssPercentile: 0.32951
ingestedAt: '2026-10-15T01:08:04.207Z'
---

## Overview

A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The socket buffer (skb) was assumed to be associated with a device before calling __ip_options_compile, which is not always the case if the skb is re-routed by ipvs. This issue may allow a local user with CAP_NET_ADMIN privileges to crash the system.

## Affected

- `linux_kernel < 6.6`
- `linux_kernel = 6.6`
- `enterprise_linux = 8.0`
- `enterprise_linux = 9.0`
- `fedora = 37`
- `fedora = 38`
- `fedora = 39`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.6`