CVE-2020-3255 json
Cisco Firepower Threat Defense Software Packet Flood Denial of Service Vulnerability
published 2020-05-06 6 y ago modified 2026-08-11 2 mo ago also EUVD-2020-24526
- cvss
- 7.5
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.9%
- EPSS 1.9% chance of exploitation in 30 days, percentile 79%
- public exploits
- 0
- none known
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.
Patch / fix
- cisco secure_firewall_threat_defense 6.2.3.16, 6.3.0.6, 6.4.0.9
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 23 mo ago
Exploit prediction
1.86% chance of exploitation in the next 30 days, higher than 79% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Cisco Cisco Firepower Threat Defense Software
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
Sources
- CVE List CVE-2020-3255
- NVD CVE-2020-3255
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