SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2022-20623

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.

HIGH 7.5EPSS 11.9%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 11.9%, higher than 96% of all known CVEs. Patch or mitigate before the next change window.

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.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
11.86% probability · 96th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-399
Affected
cisco/nx-os
Source
psirt@cisco.com
EPSS trend
0%8%15%3 November 2026: 11.86%3 November 20263 November 2026

EPSS 11.9% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.