---
id: CVE-2026-80996
title: 'net: l2tp: do not propagate multicast notification errors'
summary: |-
  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 notifica…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe:
  - CWE-770
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b <
    7efe1c31e0903a5aa796feb96d3adab574b7ff41
  - >-
    Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b <
    0fe037d5eaad938aa3e9143ee071aa237750b42b
  - >-
    Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b <
    9c340473f4822bb31b151c19afd17448eda5acd1
  - >-
    Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b <
    50c4038f1670bf9a80c6a58ae83d1602decd8481
  - >-
    Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b <
    af20e269f7459d2ce69887fdf2fad7caf986c865
  - Linux 4.0
published: '2026-09-11'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T12:47:23.378Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-80996'
references:
  - url: 'https://git.kernel.org/stable/c/7efe1c31e0903a5aa796feb96d3adab574b7ff41'
  - url: 'https://git.kernel.org/stable/c/0fe037d5eaad938aa3e9143ee071aa237750b42b'
  - url: 'https://git.kernel.org/stable/c/9c340473f4822bb31b151c19afd17448eda5acd1'
  - url: 'https://git.kernel.org/stable/c/50c4038f1670bf9a80c6a58ae83d1602decd8481'
  - url: 'https://git.kernel.org/stable/c/af20e269f7459d2ce69887fdf2fad7caf986c865'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80996.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-80996'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532170'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-80996'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80996'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-80996.mbox
tags:
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00168
epssPercentile: 0.06158
ingestedAt: '2026-09-14T00:35:28.531Z'
---

## Overview

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.

## Affected

- `Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b < 7efe1c31e0903a5aa796feb96d3adab574b7ff41`
- `Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b < 0fe037d5eaad938aa3e9143ee071aa237750b42b`
- `Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b < 9c340473f4822bb31b151c19afd17448eda5acd1`
- `Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b < 50c4038f1670bf9a80c6a58ae83d1602decd8481`
- `Linux >= 33f72e6f0c67f673fd0c63a8182dbd9ffb8cf50b < af20e269f7459d2ce69887fdf2fad7caf986c865`
- `Linux 4.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80996.json)