Improper input validation in Linux kernel - CVE-2026-46266

 

Improper input validation in Linux kernel - CVE-2026-46266

Published: June 4, 2026


Vulnerability identifier: #VU133323
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-46266
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel

Detailed vulnerability description

The vulnerability allows a remote attacker to alter forwarding and path MTU exception handling state.

The vulnerability exists due to improper input validation in RAW socket handling in the IPv4 and IPv6 ICMP error delivery paths when processing malicious incoming ICMP packets with an embedded packet header using protocol 255. A remote attacker can send a specially crafted ICMP packet to alter forwarding and path MTU exception handling state.

Exploitation requires the presence of a RAW socket created with IPPROTO_RAW.


How to mitigate CVE-2026-46266

Install security update from vendor's repository.

Sources