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

CVE-2021-40085 is fixed in 17 products on 1 platform, first by neutron-common 2:12.1.1-0ubuntu8.1, released March 6, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-40085
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0187
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 31, 2021

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | neutron-common Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-common 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-common-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-common Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-common 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-common-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-dhcp-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-dhcp-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-dhcp-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-dhcp-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-dhcp-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-dhcp-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-l3-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-l3-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-l3-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-l3-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-l3-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-l3-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-linuxbridge-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-linuxbridge-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-linuxbridge-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-linuxbridge-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-linuxbridge-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-linuxbridge-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-macvtap-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-macvtap-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-macvtap-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-macvtap-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-macvtap-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-macvtap-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-metadata-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-metadata-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-metadata-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-metadata-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-metadata-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-metadata-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-metering-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-metering-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-metering-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-metering-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-metering-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-metering-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-openvswitch-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-openvswitch-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-openvswitch-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-openvswitch-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-openvswitch-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-openvswitch-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-ovn-metadata-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-ovn-metadata-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-ovn-metadata-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-plugin-linuxbridge-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-plugin-linuxbridge-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-plugin-linuxbridge-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-plugin-ml2 Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-plugin-ml2 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-plugin-ml2-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-plugin-ml2 Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-plugin-ml2 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-plugin-ml2-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-plugin-openvswitch-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-plugin-openvswitch-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-plugin-openvswitch-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-plugin-sriov-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-plugin-sriov-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-plugin-sriov-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-server Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-server 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-server-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-server Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-server 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-server-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | neutron-sriov-agent Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [neutron-sriov-agent 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neutron-sriov-agent-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | neutron-sriov-agent Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [neutron-sriov-agent 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neutron-sriov-agent-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |
| Linux | python-neutron Ubuntu 18.04.6 LTS (bionic) | 2:12.1.1-0ubuntu8.1 | [python-neutron 2:12.1.1-0ubuntu8.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python-neutron-2-12.1.1-0ubuntu8.1.md) | Mar 6, 2023 |
| Linux | python3-neutron Ubuntu 20.04 LTS (focal) | 2:16.4.2-0ubuntu6.2 | [python3-neutron 2:16.4.2-0ubuntu6.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python3-neutron-2-16.4.2-0ubuntu6.2.md) | Mar 6, 2023 |

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