Cisco ASA Uncontrolled Resource Consumption (CVE-2020-3572)

high Tenable OT Security Plugin ID 506169

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability in the SSL/TLS session handler 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 on an affected device. The vulnerability is due to a memory leak when closing SSL/TLS connections in a specific state. An attacker could exploit this vulnerability by establishing several SSL/TLS sessions and ensuring they are closed under certain conditions. A successful exploit could allow the attacker to exhaust memory resources in the affected device, which would prevent it from processing new SSL/TLS connections, resulting in a DoS. Manual intervention is required to recover an affected device.

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.

See Also

http://www.nessus.org/u?574e4ada

Plugin Details

Severity: High

ID: 506169

File Name: tenable_ot_cisco_CVE-2020-3572.nasl

Version: 1.1

Type: Remote

Family: Tenable.ot

Published: 10/6/2026

Updated: 10/6/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3.3

Percentile: 50.87

CVSS v2

Risk Factor: Medium

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2020-3572

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:9

Required KB Items: Tenable.ot/Cisco

Patch Publication Date: 10/21/2020

Vulnerability Publication Date: 10/21/2020

Reference Information

CVE: CVE-2020-3572

CWE: 400, 401