CVE-2022-20623: Cisco Nexus 9000 Series Switches Bidirectional Forwarding Detection Denial of Service Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 11.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-02-23 · updated 2026-06-17
Weakness: CWE-399

Description

A vulnerability in the rate limiter for Bidirectional Forwarding Detection (BFD) traffic of Cisco NX-OS Software for Cisco Nexus 9000 Series Switches could allow an unauthenticated, remote attacker to cause BFD traffic to be dropped on an affected device. This vulnerability is due to a logic error in the BFD rate limiter functionality. An attacker could exploit this vulnerability by sending a crafted stream of traffic through the device. A successful exploit could allow the attacker to cause BFD traffic to be dropped, resulting in BFD session flaps. BFD session flaps can cause route instability and dropped traffic, resulting in a denial of service (DoS) condition. This vulnerability applies to both IPv4 and IPv6 traffic.

Affected products

Cisco NX-OS: from 7.0\(3\)i6\(2\) through 7.0\(3\)i7\(3\); from 7.0\(3\)i6\(2\) through 9.3\(8\); from 10.1\(1\) through 10.2\(1\)

References

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