CVE-2021-20267 Openstack Neutron has Insufficient Verification of IPv6 addresses
Attackers can impersonate IPv6 addresses via crafted packets in Open vSwitch deployments, causing denial of service or traffic interception.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-20267?
CVE-2021-20267 is a high-severity vulnerability in openstack-neutron, published on 28 May 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in openstack-neutron's default Open vSwitch firewall rules. By sending carefully crafted packets, anyone in control of a server instance connected to the virtual switch can impersonate the IPv6 addresses of other systems on the network, resulting in denial of service or in some cases possibly interception of traffic intended for other destinations. Only deployments using the Open vSwitch driver are affected. Source: OpenStack project. Versions before openstack-neutron 15.3.3, openstack-neutron 16.3.1 and openstack-neutron 17.1.1 are affected.
Weakness: CWE-345
Which versions are affected by CVE-2021-20267?
7 open source packages ship an affected version, including neutron. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
neutron PyPI | All versions | 15.3.3, 16.3.1, 17.1.1 |
neutron PyPI | All versions | 15.3.3 |
neutron PyPI | All versions | 15.3.3 |
neutron PyPI | From 16.0.0 | 16.3.1 |
neutron PyPI | From 16.0.0 | 16.3.1 |
neutron PyPI | From 17.0.0 | 17.1.1 |
1 more packages
neutron PyPI | From 17.0.0 | 17.1.1 |
Products include Openstack Neutron, Redhat Openstack Platform.
How do I fix CVE-2021-20267?
Upgrade neutron to a fixed version for your release line: 15.3.3, 16.3.1 or 17.1.1.
Is CVE-2021-20267 being exploited?
There is no known exploitation of CVE-2021-20267 in the wild and no public exploit code.
Other vulnerabilities in openstack-neutron
- CVE-2021-38598 OpenStack Neutron vulnerable to hardware address impersonation
- CVE-2015-8914 OpenStack Neutron allows remote attackers to bypass an intended ICMPv6-spoofing protection mechanism
- CVE-2016-5362 OpenStack Neutron allows remote attackers to bypass an intended DHCP-spoofing protection mechanism
- CVE-2016-5363 OpenStack Neutron Intended MAC-spoofing protection mechanism bypass
- CVE-2014-3632 Privilege escalation in n/a
Sources
Also known as DEBIAN-CVE-2021-20267, GHSA-w8hx-f868-pvch, PYSEC-2021-136, UBUNTU-CVE-2021-20267.