TI-2020-03107 Aliases CVE-2020-3563 GHSA-x72c-fv45-75v9

Cisco Firepower Threat Defense Software TCP Flood Denial of Service Vulnerability

MEDIUM 46CWE-400Published 2020-10-21 · Updated 2024-11-13

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 large number of TCP packets to a specific port on an affected device. A successful exploit could allow the attacker to exhaust system memory, which could cause the device to reload unexpectedly. No manual intervention is needed to recover the device after it has reloaded.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.01427 73rd percentileScored 2026-11-08

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 · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:cisco:secure_firewall_threat_defense::::::::	6.3.0 to before 6.3.0.6; 6.4.0 to before 6.4.0.10; 6.5.0 to before 6.5.0.5	Vulnerable	Cisco

cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions 6.3.0 to before 6.3.0.6; 6.4.0 to before 6.4.0.10; 6.5.0 to before 6.5.0.5 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2020-3563
2026-10-03 Alias added: GHSA-x72c-fv45-75v9

References

Advisory 1

20201021 Cisco Firepower Threat Defense Software TCP Flood Denial of Service Vulnerability

TI-2025-14628 Buffer overflow in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.9
TI-2021-19919 Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpoints KEVCVSS 3.1CRITICAL 10.0
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

See all 276 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences