---
id: CVE-2026-99031
title: 'net: bridge: avoid recursive multicast port cleanup'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: bridge: avoid recursive multicast port cleanup

  br_multicast_sg_del_exclude_ports() removes automatically added STAR_EXCL
  port groups by calling br_multicast_del_p…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b <
    695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64
  - >-
    Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b <
    2fb87c6025f90191516bee3ce14b42eb3e1cfed7
  - >-
    Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b <
    d109141ba14652146089ef78b32d5e4d5285ebad
  - >-
    Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b <
    7931fb9181421953f3133b408b0f2e2b8dd68b61
  - >-
    Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b <
    5158353121bae4f552cb677ce8c5c3ef52f93a0d
  - Linux 5.10
published: '2026-10-23'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T12:21:31.535Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-99031'
references:
  - url: 'https://git.kernel.org/stable/c/695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64'
  - url: 'https://git.kernel.org/stable/c/2fb87c6025f90191516bee3ce14b42eb3e1cfed7'
  - url: 'https://git.kernel.org/stable/c/d109141ba14652146089ef78b32d5e4d5285ebad'
  - url: 'https://git.kernel.org/stable/c/7931fb9181421953f3133b408b0f2e2b8dd68b61'
  - url: 'https://git.kernel.org/stable/c/5158353121bae4f552cb677ce8c5c3ef52f93a0d'
tags:
  - cve.org
ingestedAt: '2026-10-23T13:24:55.533Z'
---

## Overview

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

net: bridge: avoid recursive multicast port cleanup

br_multicast_sg_del_exclude_ports() removes automatically added STAR_EXCL
port groups by calling br_multicast_del_pg(). For S,G entries, that
deletion calls back into br_multicast_sg_del_exclude_ports(), so a large
number of STAR_EXCL ports consumes one kernel stack frame per port and can
hit the stack guard page.

Keep the complete port-group deletion path for cleanup, but suppress the
S,G exclude-port cleanup while that helper is already walking the same
entry. Normal deletion callers retain the existing behavior.

## Affected

- `Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b < 695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64`
- `Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b < 2fb87c6025f90191516bee3ce14b42eb3e1cfed7`
- `Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b < d109141ba14652146089ef78b32d5e4d5285ebad`
- `Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b < 7931fb9181421953f3133b408b0f2e2b8dd68b61`
- `Linux >= 8266a0491e92d39dc9af739e8380a0daa9b8836b < 5158353121bae4f552cb677ce8c5c3ef52f93a0d`
- `Linux 5.10`

## Remediation

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