CVE-2021-20267
7.1 · HIGHOverview
CVE-2021-20267 is a high-severity vulnerability affecting openstack neutron. It was published on May 28, 2021 and has a CVSS 3.1 base score of 7.1 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from openstack. Update neutron to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| openstack | neutron | >= 0, < 16.3.3 | Affected |
Frequently Asked Questions
What is CVE-2021-20267?
CVE-2021-20267 is a high-severity vulnerability affecting openstack neutron. It was published on May 28, 2021 and has a CVSS 3.1 base score of 7.1 (HIGH).
How severe is CVE-2021-20267?
This vulnerability has a CVSS 3.1 base score of 7.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2021-20267?
Check the references section for vendor advisories and patches from openstack. Update neutron to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-20267?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-20267 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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