ZDF
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2026-20173

Cisco NX-OS Software Control Plane Denial of Service Vulnerability

Published Oct 7, 2026 · Cisco

Check if you run it

No confirmed exploitation is on record for CVE-2026-20173. EPSS is 0.37%. Act only if a listed version of Cisco is installed.

Gaps on this record

  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Unknown—
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.37%
Remediation
Not established
Affected products
Cisco

A vulnerability in Cisco NX-OS Software could allow an unauthenticated, remote attacker to exhaust system resources, causing a denial of service (DoS) condition. This vulnerability exists because rate limiting was improperly applied to some protocols. An attacker could exploit this vulnerability by sending a high rate of UDP or TCP connections to a data plane interface on an affected device. A successful exploit could allow the attacker to cause instability to various routing and control plane protocols through some packet loss and temporary disruptions, causing a DoS condition. This

No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.

How to fix CVE-2026-20173

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-20173. EPSS is 0.37%. Act only if a listed version of Cisco is installed.

Which versions are affected?

Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 0.37%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Technology hubs

Cisco security

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 7, 2026 · Cisco Security Advisories

    Detected

    A vulnerability in Cisco NX-OS Software could allow an unauthenticated, remote attacker to exhaust system resources, causing a denial of service (DoS) condition. This vulnerability exists because rate limiting was improperly applied to some protocols. An attacker could exploit this vulnerability by sending a high rate of UDP or TCP connections to a data plane interface on an affected device. A suc

Sources

  • Cisco Security AdvisoriesVendor advisoryCVE-2026-20173

    On October 7, 2026, the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate the vulnerabilities that were disclosed on October 7, 2026, Cisco strongly recommends that customers upgrade to the fixed s

    sec.cloudapps.cisco.com
  • CVE.orgVulnerability recordCVE-2026-20173

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-20173

    30-day exploitation probability 0.4%

    first.org

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.