CVE-2026-53249

ipv4: restrict IPOPT_SSRR and IPOPT_LSRR options

MEDIUM
5.5
CVSS Score
Published: June 25, 2026 at 08:39 AM UTC
Updated: October 15, 2026 at 02:20 AM UTC
4 products affected across 2 vendorsLinux KernelSIMATIC S7-1500 CPU 1518-4 Pn /dp MFP FirmwareSiplus S7-1500 CPU 1518-4 Pn /dp MFP Firmware

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Severity
MEDIUM5.5
Exploit prediction
EPSS 0.1%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

2.6.12.1 ≤ v < 5.10.2595.11 ≤ v < 5.15.2105.16 ≤ v < 6.1.1766.13 ≤ v < 6.18.366.19 ≤ v < 7.0.136.2 ≤ v < 6.6.1436.7 ≤ v < 6.12.941da177e4c3f41524e886b7f1b8a0c1fc7321cac22.6.122.6.12 rc22.6.12 rc32.6.12 rc42.6.12 rc57.17.1 rc17.1 rc27.1 rc37.1 rc47.1 rc57.1 rc6
Vendor states this is fixed in 00e8845fe3428c69e980dce5071cb3da1d8f7578 (fixed)
Vendor states this is fixed in 28f5ad1b4055405eb1616e603fe511ba5e3725e7 (fixed)
Vendor states this is fixed in 2a87c3e8f03ce655ed0ef500d64d5fd924ec3691 (fixed)
Vendor states this is fixed in 4cd6e9ed49347d3a2fdaaf07e32fb524756dddc2 (fixed)
Vendor states this is fixed in 89343ff12b3178fc236fe531a3603e7c97c68278 (fixed)
Vendor states this is fixed in 8ff85dbabbbfb05e86e6cde31d91ac5782179d4d (fixed)
Vendor states this is fixed in a4f3fd6516920988c47ba8d19714985c40c816a1 (fixed)
Vendor states this is fixed in d3915a1f5a4bc0ac911032903c3c6ab8df9fcc7c (fixed)
Vendor states this is fixed in 2.6.12 (unaffected)
Vendor states this is fixed in 5.10.259 (unaffected)
Vendor states this is fixed in 5.15.210 (unaffected)
Vendor states this is fixed in 6.1.176 (unaffected)
Vendor states this is fixed in 6.12.94 (unaffected)
Vendor states this is fixed in 6.18.36 (unaffected)
Vendor states this is fixed in 6.6.143 (unaffected)
Vendor states this is fixed in 7.0.13 (unaffected)
Vendor states this is fixed in 7.1 (unaffected)

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
NVD-CWE-noinfo

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