Cisco ASA/FTD Web Services Infinite Loop (CVE-2024-20353)

high Tenable OT Security Plugin ID 505549

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability in the management and VPN web servers for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to incomplete error checking when parsing an HTTP header. An attacker could exploit this vulnerability by sending a crafted HTTP request to a targeted web server on a device. A successful exploit could allow the attacker to cause a DoS condition when the device reloads. Note: This vulnerability was publicly disclosed in conjunction with the ArcaneDoor state-sponsored espionage campaign that targeted perimeter network devices.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Refer to the vendor advisory.

Plugin Details

Severity: High

ID: 505549

File Name: tenable_ot_cisco_CVE-2024-20353.nasl

Version: 1.1

Type: Remote

Family: Tenable.ot

Published: 7/20/2026

Updated: 7/20/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: High

Score: 7.3

Percentile: 98.46

CVSS v3

Risk Factor: High

Base Score: 8.6

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Vulnerability Information

CPE: cpe:/o:cisco:adaptive_security_appliance_software, cpe:/o:cisco:firepower_threat_defense

Required KB Items: Tenable.ot/Cisco

Patch Publication Date: 4/24/2024

Vulnerability Publication Date: 4/24/2024

CISA Known Exploited Vulnerability Due Dates: 5/1/2024

Reference Information

CVE: CVE-2024-20353

CWE: 835

Detections

Analytics