Advisories

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software SSL VPN Denial of Service Vulnerability

Update for September 16, 2026: The original 1.0 version of this advisory was specific to the Cisco Adaptive Security Virtual Appliance (ASAv) and Cisco Secure Firewall Threat Defense Virtual (FTDv) models. However, it was later found that this vulnerability affects all Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software platforms. A vulnerability in the VPN and management web servers of the Cisco Secure Firewall ASA Software and Cisco Secure FTD Software platforms could allow an unauthenticated, remote attacker to cause an affected device to run out of system memory or buffer blocks, which in turn could cause SSL VPN connec

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-2024-20260 on this site · NVD · CVE.org · Vulnpedia

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