CVE-2025-20241 | Cisco NX-OS Software - IS-IS Operational Intel

Executive Risk Summary

"A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) feature of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause the IS-IS process to unexpectedly restart, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient input validation when parsing an ingress IS-IS packet."

Operational Audit Arsenal

Target Type Firmware Image

Target Asset Cisco NX-OS Software

Standard Path Global Firmware

Manual Verification Required

This is a non-Windows asset (Cisco). Use the target asset details and official path provided above to verify your current version against the official vendor advisories listed below.

Patch Impact Forecast

Reboot Required Likely

Network disruption possible due to device reload

Internal Work Notes

CVE-2025-20241: Cisco NX-OS Software IS-IS vulnerability, potential for denial of service (DoS) condition, requires firmware update

Technical Intelligence & Operational Utilities • Delivered Weekly

Intelligence Sources

Official Advisoryhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n39k-isis-dos-JhJA8Rfx

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Data compiled from NVD, MSRC, and CISA KEV Catalog. Intelligence synthesized via AI. Scripts provided for diagnostic purposes under MIT License.