Cisco Firepower Threat Defense Software Packet Flood Denial of Service Vulnerability
Priority MEDIUM 43CWE-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 packet processing functionality of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to inefficient memory management. An attacker could exploit this vulnerability by sending a high rate of IPv4 or IPv6 traffic through an affected device. This traffic would need to match a configured block action in an access control policy. An exploit could allow the attacker to cause a memory exhaustion condition on the affected device, which would result in a DoS for traffic transiting the device, as well as sluggish performance of the management interface. Once the flood is stopped, performance should return to previous states.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01856 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 Firepower Threat Defense Software | all versions | — | No fix listed | CNA |
- Cisco Firepower Threat Defense Software VendorCisco Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 25
| 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 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:asa_5505_firmware:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5505:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5510_firmware:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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 Vulnerable ·Cisco
- cpe:2.3:o:cisco:asa_5505_firmware:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) Vulnerable ·Cisco
Show 15 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:h:cisco:asa_5520:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:o:cisco:asa_5525-x_firmware:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | 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:9.10\(1.3\):*:*:*:*:*:*:* | 9.10(1.3) | Vulnerable | Cisco |
| cpe:2.3:h:cisco:asa_5585-x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) 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:9.10\(1.3\):*:*:*:*:*:*:* Versions 9.10(1.3) Vulnerable ·Cisco
- cpe:2.3:h:cisco:asa_5585-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-3255
- 2026-10-03 Alias added: GHSA-fwmm-vfgg-4f84
References
More Cisco Asa 5505 Firmware vulnerabilities
- TI-2020-02748 Path traversal in Cisco Adaptive Security Appliance Software CVSS 3.1CRITICAL 9.1
- TI-2021-17312 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SSL/TLS Denial of Service Vulnerability CVSS 3.1HIGH 8.6
- TI-2020-02841 Cisco Firepower 1000 Series SSL/TLS Denial of Service Vulnerability CVSS 3.1HIGH 8.6
- TI-2020-02757 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SSL/TLS Denial of Service Vulnerability CVSS 3.1HIGH 8.6
- TI-2020-02752 Improper input validation in Cisco Adaptive Security Appliance Software CVSS 3.1HIGH 8.6
- TI-2020-02750 Cisco Firepower Threat Defense Software VPN System Logging Denial of Service Vulnerability CVSS 3.1HIGH 8.6
Sources
- CVE-2020-3255 · CVE Program
- CVE-2020-3255 · NVD
- FIRST EPSS
- GHSA-fwmm-vfgg-4f84 · 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