CVE-2022-20623Network attack vector

Routing disruption via BFD rate-limiter logic error

Published Feb 23, 2022 · Updated Nov 6, 2024

Denial of service in Cisco NX-OS Software on affected Nexus 9000 switches allows remote attackers to disrupt routing with crafted traffic. A logic error in the BFD traffic rate limiter drops BFD packets under a crafted IPv4 or IPv6 stream, flapping active BFD sessions and destabilizing routes. Exploitation requires standalone NX-OS mode, an enabled BFD feature with an active session, and supported Cisco Cloud Scale ASIC hardware.

CVSS severity8.6
High
EPSS probability11.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in Cisco NX-OS Software on affected Nexus 9000 switches allows remote attackers to disrupt routing with crafted traffic. A logic error in the BFD traffic rate limiter drops BFD packets under a crafted IPv4 or IPv6 stream, flapping active BFD sessions and destabilizing routes. Exploitation requires standalone NX-OS mode, an enabled BFD feature with an active session, and supported Cisco Cloud Scale ASIC hardware.

The record

CVE
CVE-2022-20623
Published
Feb 23, 2022
Updated
Nov 6, 2024
Vendor
ClamAV
Product
Cisco NX-OS Software
Classifications
CWE-399, T1498
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 23, 2022CVE publishedPublication date reported by the CVE source.
  2. Nov 6, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco NX-OS Softwareversion=n/a

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.6CiscoCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X
7.1NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-399Resource Management Errors
T1498Network Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo