---
id: CVE-2022-50043
title: 'net: fix potential refcount leak in ndisc_router_discovery()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: fix potential refcount leak in ndisc_router_discovery()

  The issue happens on specific paths in the function. After both the
  object `rt` and `neigh` are grabbed su…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 6b2e04bc240fe9be9e690059f710e9f95346d34d <
    ffb15594433391fd7885eb88ce5a7f7bdeefbb15
  - >-
    Linux >= 6b2e04bc240fe9be9e690059f710e9f95346d34d <
    7998043d31d000c3a93f46182e6569dd0eecda34
  - >-
    Linux >= 6b2e04bc240fe9be9e690059f710e9f95346d34d <
    7396ba87f1edf549284869451665c7c4e74ecd4f
  - Linux 5.12
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T19:53:20.660559Z'
published: '2025-06-18'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T20:00:14.681Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2022-50043'
references:
  - url: 'https://git.kernel.org/stable/c/ffb15594433391fd7885eb88ce5a7f7bdeefbb15'
  - url: 'https://git.kernel.org/stable/c/7998043d31d000c3a93f46182e6569dd0eecda34'
  - url: 'https://git.kernel.org/stable/c/7396ba87f1edf549284869451665c7c4e74ecd4f'
tags:
  - cve.org
epss: 0.00195
epssPercentile: 0.09231
ingestedAt: '2026-11-05T22:38:31.638Z'
---

## Overview

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

net: fix potential refcount leak in ndisc_router_discovery()

The issue happens on specific paths in the function. After both the
object `rt` and `neigh` are grabbed successfully, when `lifetime` is
nonzero but the metric needs change, the function just deletes the
route and set `rt` to NULL. Then, it may try grabbing `rt` and `neigh`
again if above conditions hold. The function simply overwrite `neigh`
if succeeds or returns if fails, without decreasing the reference
count of previous `neigh`. This may result in memory leaks.

Fix it by decrementing the reference count of `neigh` in place.

## Affected

- `Linux >= 6b2e04bc240fe9be9e690059f710e9f95346d34d < ffb15594433391fd7885eb88ce5a7f7bdeefbb15`
- `Linux >= 6b2e04bc240fe9be9e690059f710e9f95346d34d < 7998043d31d000c3a93f46182e6569dd0eecda34`
- `Linux >= 6b2e04bc240fe9be9e690059f710e9f95346d34d < 7396ba87f1edf549284869451665c7c4e74ecd4f`
- `Linux 5.12`

## Remediation

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