Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SSL/TLS Denial of Service Vulnerability
Priority MEDIUM 47CWE-400Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-400.
Summary
A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) handler of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust memory resources on the affected device, leading to a denial of service (DoS) condition. The vulnerability is due to improper resource management for inbound SSL/TLS connections. An attacker could exploit this vulnerability by establishing multiple SSL/TLS connections with specific conditions to the affected device. A successful exploit could allow the attacker to exhaust the memory on the affected device, causing the device to stop accepting new SSL/TLS connections and resulting in a DoS condition for services on the device that process SSL/TLS traffic. Manual intervention is required to recover an affected device.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01912 79th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Cisco | Cisco Adaptive Security Appliance (ASA) Software | all versions | — | No fix listed | CNA |
- Cisco Adaptive Security Appliance (ASA) Software VendorCisco Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 50
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* | 6.2.3 to before 6.2.3.16; 6.3.0 to before 6.3.0.6; 6.4.0 to before 6.4.0.9; 6.5.0 to before 6.5.0.5 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5505_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5505_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5505_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5505:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5510_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5510_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5510_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5510:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5512-x_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
- cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions 6.2.3 to before 6.2.3.16; 6.3.0 to before 6.3.0.6; 6.4.0 to before 6.4.0.9; 6.5.0 to before 6.5.0.5 Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5505_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5505_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5505_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5505:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5510_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5510_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5510_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5510:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5512-x_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
Show 40 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:asa_5512-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5512-x_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5512-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5515-x_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5515-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5515-x_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5515-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5520_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5520_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5520_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5520:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5525-x_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5525-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5525-x_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5525-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5540_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5540_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5540_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5540:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5545-x_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5545-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5545-x_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5545-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5550_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5550_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5550_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5550:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5555-x_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5555-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5555-x_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5555-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5580_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5580_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5580_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5580:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5585-x_firmware:9.4\(4\):*:*:*:*:*:*:* | 9.4(4) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5585-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* | 9.8(4.18) | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5585-x_firmware:100.13\(0\):*:*:*:*:*:*:* | 100.13(0) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5585-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* | 9.6 to before 9.6.4.40; 9.8 to before 9.8.4.20; 9.9 to before 9.9.2.66; 9.10 to before 9.10.1.37; 9.12 to before 9.12.3.2; 9.13 to before 9.13.1.7 | Vulnerable | Cisco |
- cpe:2.3:o:cisco:asa_5512-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5512-x_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5512-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5515-x_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5515-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5515-x_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5515-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5520_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5520_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5520_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5520:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5525-x_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5525-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5525-x_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5525-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5540_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5540_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5540_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5540:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5545-x_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5545-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5545-x_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5545-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5550_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5550_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5550_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5550:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5555-x_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5555-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5555-x_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5555-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5580_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5580_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5580_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5580:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:asa_5585-x_firmware:9.4\(4\):*:*:*:*:*:*:* Versions 9.4(4) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5585-x_firmware:9.8\(4.18\):*:*:*:*:*:*:* Versions 9.8(4.18) Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5585-x_firmware:100.13\(0\):*:*:*:*:*:*:* Versions 100.13(0) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5585-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* Versions 9.6 to before 9.6.4.40; 9.8 to before 9.8.4.20; 9.9 to before 9.9.2.66; 9.10 to before 9.10.1.37; 9.12 to before 9.12.3.2; 9.13 to before 9.13.1.7 Vulnerable ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-3196
- 2026-10-03 Alias added: GHSA-57vc-vmwg-pg76
References
More Cisco Adaptive Security Appliance Software vulnerabilities
- TI-2025-14628 Buffer overflow in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.9
- TI-2016-05454 Buffer overflow in Cisco Adaptive Security Appliance (ASA) Software through 9.4.2.3 on… KEVCVSS 3.1HIGH 8.8
- TI-2023-06973 Authentication bypass in Cisco Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.1
- TI-2026-82192 Denial of service in Cisco Secure Firewall ASA and FTD SSL VPN KEVCVSS 3.1HIGH 8.6
- TI-2026-16533 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense… KEVCVSS 3.1HIGH 8.6
- TI-2025-14657 Missing authorization in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1HIGH 8.6
Sources
- CVE-2020-3196 · CVE Program
- CVE-2020-3196 · NVD
- FIRST EPSS
- GHSA-57vc-vmwg-pg76 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences