CVE-2026-46037: ipv4: icmp: validate reply type before using icmp_pointers

Severity: high (CVSS 8.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-27 · updated 2026-10-19
Weakness: CWE-125

Description

In the Linux kernel, the following vulnerability has been resolved: ipv4: icmp: validate reply type before using icmp_pointers Extended echo replies use ICMP_EXT_ECHOREPLY as the outbound reply type. That value is outside the range covered by icmp_pointers[], which only describes the traditional ICMP types up to NR_ICMP_TYPES. Avoid consulting icmp_pointers[] for reply types outside that range, and use array_index_nospec() for the remaining in-range lookup. Normal ICMP replies keep their existing behavior unchanged.

Affected products

Linux kernel: from 5.13 before 5.15.209; from 5.16 before 6.1.175; from 6.2 before 6.6.140; from 6.7 before 6.12.86; from 6.13 before 6.18.27; from 6.19 before 7.0.4 — fixed in 5.15.209, 6.1.175, 6.12.86, 6.18.27, 6.6.140, 7.0.4

How to fix

Upgrade to a fixed version: Linux kernel 5.15.209, 6.1.175, 6.12.86, 6.18.27. Check the vendor advisory for mitigations.

References

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