CVE-2026-80901

A flaw was found in the Linux kernel's IP Virtual Server (IPVS) component. This vulnerability involves insufficient checksum validation for Internet Control Message Protocol version 6 (ICMPv6) packets. Specifically, the system failed to properly validate checksums for ICMPv6 packets from clients and also had issues with pseudo-header calculations for ICMPv6 messages from real servers. An attacker could exploit this by sending specially crafted ICMPv6 packets, potentially leading to the processing of malformed data and unexpected network behavior.

IPVS had incomplete checksum validation for ICMPv6 and related translated traffic paths. Invalid ICMPv6 packets from clients or real servers could be processed when checksum validation was missing or did not include the IPv6 pseudo header, especially when hardware did not already validate the checksum. For the CVSS the PR:N because a remote sender only needs network reachability to an IPVS virtual service and does not need a local account on the target. The issue is network reachable when IPVS is exposed to untrusted clients or real server traffic. Impact is mainly low integrity impact through acceptance or processing of packets that should fail checksum validation. Availability impact is low in the paranoid score because incorrect ICMP handling can degrade connection behavior, but the patch does not indicate memory corruption, privilege escalation, or kernel crash.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.