High severity · published May 28, 2021
CVE-2021-20267
A flaw was found in openstack-neutron's default Open vSwitch firewall rules
7.1
CVSS
1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 63% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
Neutron · Openstack
before 16.3.3; 17.0.0 before 17.1.3; 18.0.0 · source: NVD
OP
Openstack Platform · Redhat
10.0; 13.0; 16.1; 16.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20267
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20267
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1934330
Patch
https://security.openstack.org/ossa/OSSA-2021-001.html
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