ASA / Firepower Threat Defense 6.6 vulnerabilities

5 advisories affect Cisco ASA / Firepower Threat Defense 6.6, 5 already exploited by attackers. Latest: September 25, 2025.

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Vulnerability	Severity	Affected versions
Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow Vulnerability CVE-2025-20333 · September 25, 2025	Critical 9.9 Exploited	11 versions, from 6.6.0 to 6.6.7.2
Cisco Secure Firewall Adaptive Security (ASA) Appliance and Secure Firewall Threat Defense (FTD) Missing Authorization Vulnerability CVE-2025-20362 · September 25, 2025	Medium 6.5 Exploited	11 versions, from 6.6.0 to 6.6.7.2
Cisco ASA and FTD Denial-of-Service Vulnerability CVE-2024-20481 · October 24, 2024	Medium 5.8 Exploited	11 versions, from 6.6.0 to 6.6.7.2
Cisco ASA and FTD Denial of Service Vulnerability CVE-2024-20353 · April 24, 2024	High 8.6 Exploited	10 versions, from 6.6.0 to 6.6.7.1
Cisco ASA and FTD Privilege Escalation Vulnerability CVE-2024-20359 · April 24, 2024	Medium 6 Exploited	10 versions, from 6.6.0 to 6.6.7.1

Affected versions are compiled automatically from vendor advisories and NVD and may contain errors. Where no fixed version is shown, you will find it in the official advisory linked from every page: check it there before updating.

Other ASA / Firepower Threat Defense versions: 10.1 · 10.0 · 9.24 · 9.23 · 9.22 · 9.20 · 9.19 · 9.18 · 9.17 · 9.16 · 9.15 · 9.14 · 9.12 · 9.8 · 7.7 · 7.6 · 7.4 · 7.3 · 7.2 · 7.1 · 7.0 · 6.7 · 6.4 · 6.2