CVE-2020-3304: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Denial of Service Vulnerability

Severity: high (CVSS 8.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-21 · updated 2026-08-11
Weakness: CWE-400

Description

A vulnerability in the web interface of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. An exploit could allow the attacker to cause a DoS condition. Note: This vulnerability applies to IP Version 4 (IPv4) and IP Version 6 (IPv6) HTTP traffic.

Affected products

Cisco Adaptive Security Appliance: before 9.6.4.45 — fixed in 9.6.4.45
Cisco ASA Software: from 9.8.0 before 9.8.4.22; from 9.9.0 before 9.9.2.80; from 9.10.0 before 9.10.1.44; from 9.12.0 before 9.12.3.12; from 9.13.0 before 9.13.1.12; from 9.14.0 before 9.14.1.10 — fixed in 9.10.1.44, 9.12.3.12, 9.13.1.12, 9.14.1.10, 9.8.4.22, 9.9.2.80
Cisco Firepower Threat Defense Software: before 6.3.0.6; from 6.4.0 before 6.4.0.10; from 6.5.0 before 6.5.0.5; from 6.6.0 before 6.6.1 — fixed in 6.3.0.6, 6.4.0.10, 6.5.0.5, 6.6.1

How to fix

Upgrade to a fixed version: Cisco Adaptive Security Appliance 9.6.4.45; Cisco ASA Software 9.10.1.44, 9.12.3.12, 9.13.1.12, 9.14.1.10; Cisco Firepower Threat Defense Software 6.3.0.6, 6.4.0.10, 6.5.0.5, 6.6.1. Check the vendor advisory for mitigations.

References

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