CVE-2022-20745: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Interface Denial of Service Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-05-03 · updated 2026-08-11
Weakness: CWE-20

Description

A vulnerability in the web services interface for remote access VPN features of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper input validation when parsing HTTPS requests. An attacker could exploit this vulnerability by sending a crafted HTTPS request to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Affected products

Cisco ASA Software: before 9.12.4.38; from 9.13.0 before 9.14.4; from 9.15.0 before 9.15.1.21; from 9.16.0 before 9.16.2.14; from 9.17.0 before 9.17.1.7 — fixed in 9.12.4.38, 9.14.4, 9.15.1.21, 9.16.2.14, 9.17.1.7
Cisco Firepower Threat Defense Software: before 6.4.0.15; from 6.5.0 before 6.6.5.2; from 7.0.0 before 7.0.2; 7.1.0 — fixed in 6.4.0.15, 6.6.5.2, 7.0.2

How to fix

Upgrade to a fixed version: Cisco ASA Software 9.12.4.38, 9.14.4, 9.15.1.21, 9.16.2.14; Cisco Firepower Threat Defense Software 6.4.0.15, 6.6.5.2, 7.0.2. Check the vendor advisory for mitigations.

References

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