Linux Kernel Vulnerability Affecting ICMP Protocol Handling
CVE-2026-23398
Key Information:
Badges
What is CVE-2026-23398?
A vulnerability in the Linux kernel's ICMP protocol handling could lead to a kernel panic upon receiving specific ICMP Fragmentation Needed errors. The issue arises from the unconditional dereference of an unregistered protocol's handler, which may result in a NULL pointer dereference. This occurs particularly when the ip_no_pmtu_disc setting is configured with hardened PMTU mode. Proper checks must be implemented to ensure that the protocol has registered handlers before accessing related functions to prevent potential system crashes.
Affected Version(s)
Linux 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e < 571d9d7b650f02d1e38c01128817868bceac9edd
Linux 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e
Linux 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e < 1f9f2c6d4b2a613b7756fc5679c5116ba2ca0161
Exploit Proof of Concept (PoC)
PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.