CVE-2021-40085: Medium severity Openstack Neutron vulnerability

Q: What is CVE-2021-40085?

CVE-2021-40085 is a vulnerability discovered in OpenStack Neutron that allows authenticated attackers to reconfigure dnsmasq via a crafted extra_dhcp_opts value.

Q: How can the CVE-2021-40085 vulnerability be exploited?

The CVE-2021-40085 vulnerability can be exploited by authenticated attackers who can manipulate the extra_dhcp_opts value to reconfigure dnsmasq.

Q: What is the severity of CVE-2021-40085?

The severity of CVE-2021-40085 is medium, with a severity value of 6.5.

Q: Which versions of OpenStack Neutron are affected by CVE-2021-40085?

OpenStack Neutron versions before 16.4.1, 17.x before 17.2.1, and 18.x before 18.1.1 are affected by CVE-2021-40085.

Q: How can I fix the CVE-2021-40085 vulnerability?

To fix the CVE-2021-40085 vulnerability, update your OpenStack Neutron to version 16.4.1, 17.2.1, or 18.1.1.

Published Aug 31, 2021

Updated

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 extradhcpopts value.

Affected Software

11 affected componentsFixes available

debian/neutron

2:13.0.7+git.2021.09.27.bace3d1890-0+deb10u12:17.2.1-0+deb11u12:21.0.0-72:23.0.0-2

debian/neutron<=2:17.1.1-6, <=2:18.1.0-2

2:18.1.0-32:13.0.7+git.2021.09.27.bace3d1890-0+deb10u12:19.0.0~rc1-12:17.2.1-0+deb11u1

pip/neutron>=18.0.0<18.1.1

18.1.1

pip/neutron>=17.0.0<17.2.1

17.2.1

pip/neutron<16.4.1

16.4.1

Openstack Neutron<16.4.1

Openstack Neutron>=17.0.0<17.2.1

Openstack Neutron>=18.0.0<18.1.1

Debian Debian Linux=9.0

Debian Debian Linux=10.0

Debian Debian Linux=11.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade debian/neutron to a version that resolves this vulnerability.
Fixed in 2:13.0.7+git.2021.09.27.bace3d1890-0+deb10u1Fixed in 2:17.2.1-0+deb11u1Fixed in 2:21.0.0-7Fixed in 2:23.0.0-2
Upgrade
Upgrade debian/neutron to a version that resolves this vulnerability.
Fixed in 2:18.1.0-3Fixed in 2:13.0.7+git.2021.09.27.bace3d1890-0+deb10u1Fixed in 2:19.0.0~rc1-1Fixed in 2:17.2.1-0+deb11u1
Upgrade
Upgrade pip/neutron to a version that resolves this vulnerability.
Fixed in 18.1.1
Upgrade
Upgrade pip/neutron to a version that resolves this vulnerability.
Fixed in 17.2.1
Upgrade
Upgrade pip/neutron to a version that resolves this vulnerability.
Fixed in 16.4.1
Upgrade
Upgrade OpenStack Neutron to a version that resolves this vulnerability.
Fixed in 16.4.1
Upgrade
Upgrade OpenStack Neutron to a version that resolves this vulnerability.
Fixed in 17.2.1
Upgrade
Upgrade OpenStack Neutron to a version that resolves this vulnerability.
Fixed in 18.1.1

Event History

Aug 31, 2021

CVE Published

via MITRE·05:32 PM

Data Sourced

via MITRE·05:32 PM

Description

Data Sourced

via NVD·06:15 PM

RemedyDescriptionSeverityAffected Software

May 24, 2022

Advisory Published

via GitHub·07:12 PM

Frequently Asked Questions

What is CVE-2021-40085?

CVE-2021-40085 is a vulnerability discovered in OpenStack Neutron that allows authenticated attackers to reconfigure dnsmasq via a crafted extra_dhcp_opts value.

How can the CVE-2021-40085 vulnerability be exploited?

The CVE-2021-40085 vulnerability can be exploited by authenticated attackers who can manipulate the extra_dhcp_opts value to reconfigure dnsmasq.

What is the severity of CVE-2021-40085?

The severity of CVE-2021-40085 is medium, with a severity value of 6.5.

Which versions of OpenStack Neutron are affected by CVE-2021-40085?