# CVE-2023-42754: Kernel: ipv4: null pointer dereference in ipv4_send_dest_unreach()

Status: published. Published: 2023-10-05. Updated: 2026-11-07.

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.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 8 (kernel-rt): ≥ 0:4.18.0-553.rt7.342.el8_10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (kernel): ≥ 0:4.18.0-553.el8_10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (kernel): ≥ 0:5.14.0-427.13.1.el9_4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (kernel): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (kernel): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (kernel-rt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (kernel-rt): Version range not reported. Source: CNA: redhat
- Siemens / SIMATIC S7-1500 CPU 1518-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP
- Siemens / SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP
- Siemens / SIMATIC S7-1500 TM MFP - GNU/Linux subsystem: ≥ 0; < V1.1 (affected, custom). Source: ADP: siemens-SADP
- Siemens / SIPLUS S7-1500 CPU 1518-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP

## Severity and prioritization

- CVSS 3.1: 5.5 (medium); CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.43% as of 2026-11-06; percentile 36.96%

- SSVC: Not available

- Weaknesses: CWE-476

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2024:2394 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:2950 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3138 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-42754 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2239845 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://seclists.org/oss-sec/2023/q4/14 (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2024:2394 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:2950 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3138 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-42754 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2239845 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GISYSL3F6WIEVGHJGLC2MFNTUXHPTKQH/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GPMICQ2HVZO5UAM5KPXHAZKA2U3ZDOO6/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/V5PDNWPKAP3WL5RQZ4RIDS6MG32OHH5R/ (ADP: CVE; x_transferred)

- https://seclists.org/oss-sec/2023/q4/14 (ADP: CVE; x_transferred)

- https://cert-portal.siemens.com/productcert/html/ssa-794697.html (ADP: siemens-SADP)

- https://cert-portal.siemens.com/productcert/html/ssa-398330.html (ADP: siemens-SADP)

- https://cert-portal.siemens.com/productcert/html/ssa-769027.html (ADP: siemens-SADP)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-42754; retrieved 2026-11-07; source updated 2026-11-07

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-42754; retrieved 2026-11-07; source updated Not reported

Revision: be5787594fabecbaa2e2e0aed57e520c629c36881da8dd6b2e03cbf2a79c42b3

Canonical: https://y2.dev/cve/CVE-2023-42754

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