CVE-2026-43057

A flaw was found in the Linux kernel's networking subsystem. Incorrect handling of tunneled IPv6 traffic, specifically when processing packets with IPv6 extension headers or without an inner IP protocol, can cause the system to improperly revert to a software processing path. This issue may lead to a denial of service due to degraded network performance or dropped packets.

This vulnerability is rated as Moderate impact because its scope is limited to network service disruption and packet loss, with no risk to data integrity or confidentiality. Exploitation requires generating specific encapsulated IPv6 traffic, such as tunneled packets utilizing extension headers or non-standard transport protocols. Supported Red Hat Enterprise Linux releases are not affected because the upstream regression that introduced this behavior is not present in their kernel builds.

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.