Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) known exploited vulnerabilities
We track 10 CVEs in Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD). All of them are on CISA's Known Exploited Vulnerabilities catalog, meaning CISA has evidence of exploitation in the wild (listed 2021–2026). CISA flags 3 of them as used in ransomware campaigns. The most recent is CVE-2026-20349, added to KEV on .
Also listed as: Adaptive Security Appliance and Firepower Threat Defense · Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) · Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense. CISA, NVD and vendor advisories name the same product differently; each CVE page keeps the wording from its source.
- CVEs tracked
- 10
- On CISA KEV
- 10
- Ransomware use
- 3
- Rated critical
- 1
Every Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) CVE we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV | Patch by |
|---|---|---|---|---|---|
| CVE-2026-20349 Cisco ASA and FTD VPN Heap Inspection Denial-of-Service Flawwrite-up | [ HIGH ] | 8.6 | 1.0% | ||
| CVE-2025-20362 Cisco Secure Firewall Adaptive Security (ASA) Appliance and Secure Firewall Threat Defense (FTD) Missing Authorization Vulnerability | [ MEDIUM ] | 6.5 | 87.1% | ||
| CVE-2025-20333 Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow Vulnerability | [ CRITICAL ] | 9.9 | 71.2% | ||
| CVE-2024-20481 Cisco ASA and FTD Denial-of-Service Vulnerability | [ MEDIUM ] | 5.8 | 15.9% | ||
| CVE-2024-20359 Cisco ASA and FTD Privilege Escalation Vulnerability | [ MEDIUM ] | 6.0 | 19.4% | ||
| CVE-2024-20353 Cisco ASA and FTD Denial of Service Vulnerability | [ HIGH ] | 8.6 | 70.7% | ||
| CVE-2020-3259 Cisco ASA and FTD Information Disclosure Vulnerabilityransomware use | [ HIGH ] | 7.5 | 71.8% | ||
| CVE-2023-20269 Cisco Adaptive Security Appliance and Firepower Threat Defense Unauthorized Access Vulnerabilityransomware use | [ MEDIUM ] | 5.0 | 25.5% | ||
| CVE-2020-3580 Cisco ASA and FTD Cross-Site Scripting (XSS) Vulnerabilityransomware use | [ MEDIUM ] | 6.1 | 85.6% | ||
| CVE-2020-3452 Cisco ASA and FTD Read-Only Path Traversal Vulnerability | [ HIGH ] | 7.5 | 100.0% |
Sorted by date added to KEV. Severity and CVSS as stated by NVD or the vendor; EPSS from FIRST.org. "Patch by" is CISA's BOD 22-01 deadline for US federal agencies, a useful priority signal for everyone else. Machine-readable: /api/v1/vendors/cisco.json.
Our Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) coverage
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Every row links to its CVE record with the CISA required action, catalog coverage and primary sources. We describe impact and remediation only; no exploit code. See the full KEV tracker or compare KEV catalogs.