Medium 6.7Published Oct 9, 2023

CVE-2023-39192Kernel: netfilter: xtables out-of-bounds read in u32_match_it()

Updated under an hour ago (Oct 26, 2026, 4:23 PM ET)

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It affects Red Hat Enterprise Linux 8 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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Every CVE for Red Hat Enterprise Linux 8

Exploited in the last 30 days

A flaw was found in the Netfilter subsystem in the Linux kernel. The xt_u32 module did not validate the fields in the xt_u32 structure. This flaw allows a local privileged attacker to trigger an out-of-bounds read by setting the size fields with a value beyond the array boundaries, leading to a crash or information disclosure.

CVSS: 6.7 MEDIUM (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:L
Weakness (CWE): CWE-125
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: redhat
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Red Hat Red Hat Enterprise Linux 8 redhat:enterprise_linux	from 0:4.18.0-553.rt7.342.el8_10 not affected	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	before 6.6	NVD
redhat enterprise_linux redhat:enterprise_linux	8.0	NVD
fedoraproject fedora fedoraproject:fedora	38	NVD

References

References

https://access.redhat.com/errata/RHSA-2024:2950	vendor-advisory, x-refsource-redhat
https://access.redhat.com/errata/RHSA-2024:3138	vendor-advisory, x-refsource-redhat
https://access.redhat.com/security/cve/CVE-2023-39192	vdb-entry, x-refsource-redhat, third-party-advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2226784	issue-tracking, x-refsource-redhat, patch, third-party-advisory
https://www.zerodayinitiative.com/advisories/ZDI-CAN-18408/	third-party-advisory, vdb-entry
https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html
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.