Advisories

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software for Secure Firewall 3100 and 4200 Series DTLS Denial of Service Vulnerability

A vulnerability in Datagram TLS (DTLS) message handling of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software for Cisco Secure Firewall 3100 Series and 4200 Series devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper resource management when processing certain DTLS messages. An attacker could exploit this vulnerability by sending a crafted stream of DTLS traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Cisco has released softwar

Read at Cisco PSIRT Security Advisories

Vendor

Cisco

Product

ASA, Firepower / FTD

Fix

available

Exposure class

Edge / VPN / firewall

• Cisco PSIRT Security Advisories (sec.cloudapps.cisco.com)
• CVE-2026-20250 on this site · NVD · CVE.org · Vulnpedia

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