---
id: CVE-2026-72447
title: 'sctp: hold socket lock when dumping endpoints in sctp_diag'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  sctp: hold socket lock when dumping endpoints in sctp_diag

  SCTP_DIAG endpoint dumping was traversing endpoint address lists without
  holding lock_sock(), while those li…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    f98c294a9369b6fe89e652c06357ee594be4dfa2
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    8b38e3dcfde3077dbc03eb8ef88e03cc19f70b8a
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    ec3c2d59a192e17e1014ba71afc368ba162ecac3
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    722576aba0a6d9423714550b1c03239b0f0def77
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    abe7f8828e6ac8be858870c2bf836258844f97d5
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    207bb4ce8fe7de961ae7bb33569ad2cd61f44954
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    f09a245f33e567b604efa1960b7a2d25dd9c8713
  - >-
    Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef <
    7d8297e26b4e20b5d1c3c3fe51fe81a1c7fbc823
  - Linux 4.7
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T16:55:33.287440Z'
published: '2026-08-15'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T17:05:42.860Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-72447'
references:
  - url: 'https://git.kernel.org/stable/c/f98c294a9369b6fe89e652c06357ee594be4dfa2'
  - url: 'https://git.kernel.org/stable/c/8b38e3dcfde3077dbc03eb8ef88e03cc19f70b8a'
  - url: 'https://git.kernel.org/stable/c/ec3c2d59a192e17e1014ba71afc368ba162ecac3'
  - url: 'https://git.kernel.org/stable/c/722576aba0a6d9423714550b1c03239b0f0def77'
  - url: 'https://git.kernel.org/stable/c/abe7f8828e6ac8be858870c2bf836258844f97d5'
  - url: 'https://git.kernel.org/stable/c/207bb4ce8fe7de961ae7bb33569ad2cd61f44954'
  - url: 'https://git.kernel.org/stable/c/f09a245f33e567b604efa1960b7a2d25dd9c8713'
  - url: 'https://git.kernel.org/stable/c/7d8297e26b4e20b5d1c3c3fe51fe81a1c7fbc823'
tags:
  - cve.org
epss: 0.0022
epssPercentile: 0.12602
ingestedAt: '2026-11-06T18:00:12.574Z'
---

## Overview

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

sctp: hold socket lock when dumping endpoints in sctp_diag

SCTP_DIAG endpoint dumping was traversing endpoint address lists without
holding lock_sock(), while those lists could change concurrently via
socket operations (e.g., bindx changes). This creates a race where
nla_reserve() counts addresses under RCU protection, but the subsequent
copy may see fewer entries, potentially leaking uninitialized memory to
userspace.

Fix this by:

- Taking a reference on each endpoint during hash traversal
- Moving socket operations (lock_sock()) outside read_lock_bh()
- Serializing address list access during dump
- Reworking sctp_for_each_endpoint() to support restart-based traversal
  with (net, pos) tracking

Also:

- Add WARN_ON_ONCE() for inconsistent address counts
- Fix idiag_states filtering for LISTEN vs association cases
- Skip dumping endpoints being freed (ep->base.dead)
- Move dump position tracking into iterator, removing cb->args[4] and
  its comment for sctp_ep_dump().,
- Update the comment for cb->args[4] and remove the comment for unused
  cb->args[5] for sctp_sock_dump().

Note: traversal is restart-based and may re-scan buckets multiple times,
but this is acceptable due to small bucket sizes and required to support
sleeping-safe callbacks.

This issue was reported by Nico Yip (@_cyeaa_) working with TrendAI Zero
Day Initiative.

## Affected

- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < f98c294a9369b6fe89e652c06357ee594be4dfa2`
- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < 8b38e3dcfde3077dbc03eb8ef88e03cc19f70b8a`
- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < ec3c2d59a192e17e1014ba71afc368ba162ecac3`
- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < 722576aba0a6d9423714550b1c03239b0f0def77`
- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < abe7f8828e6ac8be858870c2bf836258844f97d5`
- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < 207bb4ce8fe7de961ae7bb33569ad2cd61f44954`
- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < f09a245f33e567b604efa1960b7a2d25dd9c8713`
- `Linux >= 8f840e47f190cbe61a96945c13e9551048d42cef < 7d8297e26b4e20b5d1c3c3fe51fe81a1c7fbc823`
- `Linux 4.7`

## Remediation

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