---
id: CVE-2016-5363
aliases:
  - GHSA-9pp3-cvmq-9p22
  - PYSEC-2026-852
title: OpenStack Neutron Intended MAC-spoofing protection mechanism bypass
summary: OpenStack Neutron Intended MAC-spoofing protection mechanism bypass
severity: high
cvss: 8.2
cvssVector: 'CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H'
vendor: neutron
product: neutron
ecosystem: pip
affected:
  - neutron < 7.1.0
  - 'neutron >= 8.0.0, < 8.1.0'
patched:
  - neutron 7.1.0
  - neutron 8.1.0
published: '2022-05-17'
updated: '2026-07-07'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-9pp3-cvmq-9p22'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2016-5363'
  - url: >-
      https://github.com/openstack/neutron/commit/5853af9cba6733725d6c9ac0db644f426713f0cf
  - url: >-
      https://github.com/openstack/neutron/commit/6a93ee8ac1a901c255e3475a24f1afc11d8bf80f
  - url: >-
      https://github.com/openstack/neutron/commit/997d7b03fb7f5528f0a3ce70867b9dcd9321509e
  - url: >-
      https://github.com/openstack/neutron/commit/fd5fd259a02156babdfcb12f66cde6ec9e7274ae
  - url: 'https://access.redhat.com/errata/RHSA-2016:1473'
  - url: 'https://access.redhat.com/errata/RHSA-2016:1474'
  - url: 'https://bugs.launchpad.net/neutron/+bug/1558658'
  - url: 'https://github.com/openstack/neutron'
  - url: 'https://review.openstack.org/#/c/299021'
  - url: 'https://review.openstack.org/#/c/299023'
  - url: 'https://review.openstack.org/#/c/299025'
  - url: 'https://security.openstack.org/ossa/OSSA-2016-009.html'
  - url: 'http://www.openwall.com/lists/oss-security/2016/06/10/5'
  - url: 'http://www.openwall.com/lists/oss-security/2016/06/10/6'
tags:
  - osv
  - pip
epss: 0.03486
epssPercentile: 0.88605
ingestedAt: '2026-07-08T18:25:48.061Z'
---

## Overview

The IPTables firewall in OpenStack Neutron up to 7.0.4 and 8.x before 8.1.0 allows remote attackers to bypass an intended MAC-spoofing protection mechanism and consequently cause a denial of service or intercept network traffic via (1) a crafted DHCP discovery message or (2) crafted non-IP traffic.

## Affected packages

- `neutron < 7.1.0`
- `neutron >= 8.0.0, < 8.1.0`

## Remediation

Upgrade to a patched release:

- `neutron 7.1.0`
- `neutron 8.1.0`