---
id: CVE-2026-74550
title: 'net: do not send ICMP/NDISC Redirects when peer allocation fails'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: do not send ICMP/NDISC Redirects when peer allocation fails

  When inet_getpeer_v4() or inet_getpeer_v6() fails to allocate a peer entry
  under memory pressure or tr…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 <
    c0adf8b4247bcc5a145a25c1929006eb392580bb
  - >-
    Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 <
    f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1
  - >-
    Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 <
    21666f7af49a90ef44d474916b8ef4402dfd74f5
  - >-
    Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 <
    5ec5f00fc606a6df8434948c4552b3cb1176595d
  - >-
    Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 <
    828f6670d110ff2bf44c743037b38badc315704c
  - >-
    Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 <
    dbc3791e3b2472e1ccc08947e0f83b443470ff4f
  - Linux 2.6.39
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-16T18:59:55.162783Z'
published: '2026-08-15'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T19:05:55.243Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74550'
references:
  - url: 'https://git.kernel.org/stable/c/c0adf8b4247bcc5a145a25c1929006eb392580bb'
  - url: 'https://git.kernel.org/stable/c/f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1'
  - url: 'https://git.kernel.org/stable/c/21666f7af49a90ef44d474916b8ef4402dfd74f5'
  - url: 'https://git.kernel.org/stable/c/5ec5f00fc606a6df8434948c4552b3cb1176595d'
  - url: 'https://git.kernel.org/stable/c/828f6670d110ff2bf44c743037b38badc315704c'
  - url: 'https://git.kernel.org/stable/c/dbc3791e3b2472e1ccc08947e0f83b443470ff4f'
tags:
  - cve.org
epss: 0.00479
epssPercentile: 0.399
ingestedAt: '2026-10-16T19:46:24.345Z'
---

## Overview

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

net: do not send ICMP/NDISC Redirects when peer allocation fails

When inet_getpeer_v4() or inet_getpeer_v6() fails to allocate a peer entry
under memory pressure or tree size caps, redirect handlers previously fell
back to sending un-rate-limited ICMP/NDISC Redirect messages.

In IPv4, ip_rt_send_redirect() called icmp_send() directly when peer == NULL.
In IPv6, ip6_forward() and ndisc_send_redirect() passed a NULL peer into
inet_peer_xrlim_allow(), which returned true when peer == NULL.

Because ICMP/NDISC Redirects are not part of the default global rate limit
mask (sysctl_icmp_ratemask), sending redirects when peer == NULL creates
an un-rate-limited ICMP packet storm.

Fix this by failing closed in ip_rt_send_redirect(), ip6_forward(), and
ndisc_send_redirect() when peer is NULL.

## Affected

- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < c0adf8b4247bcc5a145a25c1929006eb392580bb`
- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1`
- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 21666f7af49a90ef44d474916b8ef4402dfd74f5`
- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 5ec5f00fc606a6df8434948c4552b3cb1176595d`
- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < 828f6670d110ff2bf44c743037b38badc315704c`
- `Linux >= 92d8682926342d2b6aa5b2ecc02221e00e1573a0 < dbc3791e3b2472e1ccc08947e0f83b443470ff4f`
- `Linux 2.6.39`

## Remediation

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