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  4. CVE 2026 53249 ipv4 restrict ipoptssrr and ipoptlsrr options
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Copyright ยฉ 2026 HOL DAO LLC. All rights reserved.

Back to active CVEs
Medium ยท CVSS 5.5CVE-2026-53249

ipv4: restrict IPOPT_SSRR and IPOPT_LSRR optionsCVE-2026-53249

Answer in brief

CVE-2026-53249 records a Medium severity (CVSS 5.5) vulnerability in ipv4: restrict IPOPT_SSRR and IPOPT_LSRR options. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jun 25, 2026Updated Oct 15, 2026Source checked Oct 23, 2026First seen by HOL Jun 25, 2026Material review Oct 15, 2026
Upstream Advisory

Key facts

Risk
Medium ยท CVSS 5.5
Exploitation
Not marked as known exploited
Affected software
21 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.

Affected products and reported versions
ProductAffected versionsFixed versions
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*Not reportedNot reported
Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Linux/Linuxgeneric>=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <4cd6e9ed49347d3a2fdaaf07e32fb524756dddc2 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2a87c3e8f03ce655ed0ef500d64d5fd924ec3691 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <89343ff12b3178fc236fe531a3603e7c97c68278 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8ff85dbabbbfb05e86e6cde31d91ac5782179d4d || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <00e8845fe3428c69e980dce5071cb3da1d8f7578 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a4f3fd6516920988c47ba8d19714985c40c816a1 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <28f5ad1b4055405eb1616e603fe511ba5e3725e7 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d3915a1f5a4bc0ac911032903c3c6ab8df9fcc7c4cd6e9ed49347d3a2fdaaf07e32fb524756dddc2, 2a87c3e8f03ce655ed0ef500d64d5fd924ec3691, 89343ff12b3178fc236fe531a3603e7c97c68278, 8ff85dbabbbfb05e86e6cde31d91ac5782179d4d, 00e8845fe3428c69e980dce5071cb3da1d8f7578, a4f3fd6516920988c47ba8d19714985c40c816a1, 28f5ad1b4055405eb1616e603fe511ba5e3725e7, d3915a1f5a4bc0ac911032903c3c6ab8df9fcc7c
Linux/Linuxgeneric2.6.12Not reported
Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.6 <**
Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.7 <**
Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric>=V3.1.6 <**
Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric>=V3.1.7 <**
Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystemgeneric>=0 <**
Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.6 <**
Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.7 <**

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux, Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP.
  2. 2Review the reported fix. Update Linux/Linux to 4cd6e9ed49347d3a2fdaaf07e32fb524756dddc2; Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to *; Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP to *; Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP to * if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Jun 25, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Oct 15, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Jun 25, 2026

Sources and claim methodology

  • Source referencecert-portal.siemens.com
  • Source referencecert-portal.siemens.com
  • Source referencecert-portal.siemens.com
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
Upstream source description

In the Linux kernel, the following vulnerability has been resolved: ipv4: restrict IPOPT_SSRR and IPOPT_LSRR options This patch restricts setting Loose Source and Record Route (LSRR) and Strict Source and Record Route (SSRR) IP options to users with CAP_NET_RAW capability. This prevents unprivileged applications from forcing packets to route through attacker-controlled nodes to leak TCP ISN and possibly other protocol information. While LSRR and SSRR are commonly filtered in many network environments, they may still be supported and forwarded along some network paths. RFC 7126 (Recommendations on Filtering of IPv4 Packets Containing IPv4 Options) recommend to drop these options in 4.3 and 4.4.

Quoted source text, attributed separately from HOL analysis.

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
NVD-CWE-noinfo
Source
CVE List V5
Source checked
Oct 23, 2026
References
11 linked sources
Open source record