Home/CVE/A flaw was found in openstack-neutron's default Open vSwitch firewall rules. By sending carefully crafted packets, anyon
CVE

CVE-2021-20267

A flaw was found in openstack-neutron's default Open vSwitch firewall rules. By sending carefully crafted packets, anyon

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.

HIGH · CVSS 7.1 EPSS 0.00126
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-345Insufficient Verification of Data Authenticity
▤

Affected Products & Versions

4
openstack neutron< 16.3.3
openstack neutron>= 17.0.0 and < 17.1.3
openstack neutronall versions
redhat openstack platformall versions
▤

Affected Packages

1
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
PyPI neutron HIGH fixed in 16.3.1
▣

Scoring & Timeline

7.1
HIGH · CVSS v3.1 · secalert@redhat.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD28 May 2021 · 07:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
⚑

Vendor Advisories

1
usnUSN-6067-1
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugzilla.redhat.com/show_bug.cgi?id=1934330Issue TrackingPatchThird Party Advisory
https://security.openstack.org/ossa/OSSA-2021-001.htmlPatchVendor Advisory
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