CVSS v3
9.1
CRITICAL
EPSS Score
1.2 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
OpenStack Neutron before 16.4.1, 17.x before 17.1.3, and 18.0.0 allows hardware address impersonation when the linuxbridge driver with ebtables-nft is used on a Netfilter-based platform. By sending carefully crafted packets, anyone in control of a server instance connected to the virtual switch can impersonate the hardware addresses of other systems on the network, resulting in denial of service or in some cases possibly interception of traffic intended for other destinations.
Technical details
- Published
- 2021-08-23
Frequently asked questions
What is CVE-2021-38598?
OpenStack Neutron before 16.4.1, 17.x before 17.1.3, and 18.0.0 allows hardware address impersonation when the linuxbridge driver with ebtables-nft is used on a Netfilter-based platform. By sending carefully crafted packets, anyone in control of a server instance connected to the virtual switch can impersonate the hardware addresses of other systems on the network, resulting in denial of service or in some cases possibly interception of traffic intended for other destinations.
Is CVE-2021-38598 actively exploited?
Active exploitation of CVE-2021-38598 has not been confirmed. Its EPSS score was 1.2% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-38598?
CVE-2021-38598 has a CVSS v3 base score of 9.1 (CRITICAL severity).
Is CVE-2021-38598 affecting your environment?
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