CVE-2025-20134 | Cisco Secure Firewall - Adaptive Security Appliance (ASA) Software Operational Intel

Executive Risk Summary

"A vulnerability in the certificate processing of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper parsing of SSL/TLS certificates and can be exploited by sending crafted DNS packets."

Operational Audit Arsenal

Target Type Firmware Image

Target Asset Cisco Secure Firewall ASA 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

High

Internal Work Notes

CVE-2025-20134: Cisco Secure Firewall ASA Software vulnerability allowing remote DoS attacks via crafted DNS packets, requiring firmware update

Technical Intelligence & Operational Utilities • Delivered Weekly

Intelligence Sources

Official Advisoryhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ssltls-dos-eHw76vZe

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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.