CVE-2026-80996

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

net: l2tp: do not propagate multicast notification errors

The tunnel create, tunnel modify, session create, and session modify

netlink handlers send multicast notifications through helpers that can fail

while allocating or encoding a message, or while multicasting it.

For tunnel and session create/modify, a notification is sent after the live

operation has completed. Returning a best-effort notification error as the

command result can therefore report failure for an operation that already

committed and can cause callers to retry and accumulate live objects.

Keep sending notifications for listener visibility, but do not propagate

their best-effort status as the command result. This also keeps the tunnel

modify command consistent with the other notification-only paths.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References