Cisco ASA/FTD Observable Discrepancy (CVE-2020-3585)

low Tenable OT Security Plugin ID 506133

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability in the TLS handler of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 1000 Series firewalls could allow an unauthenticated, remote attacker to gain access to sensitive information. The vulnerability is due to improper implementation of countermeasures against the Bleichenbacher attack for cipher suites that rely on RSA for key exchange. An attacker could exploit this vulnerability by sending crafted TLS messages to the device, which would act as an oracle and allow the attacker to carry out a chosen- ciphertext attack. A successful exploit could allow the attacker to perform cryptanalytic operations that may allow decryption of previously captured TLS sessions to the affected device. To exploit this vulnerability, an attacker must be able to perform both of the following actions: Capture TLS traffic that is in transit between clients and the affected device Actively establish a considerable number of TLS connections to the 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.

Plugin Details

Severity: Low

ID: 506133

File Name: tenable_ot_cisco_CVE-2020-3585.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: 1.2

Percentile: 0.01

CVSS v2

Risk Factor: Medium

Base Score: 4.3

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

CVSS Score Source: CVE-2020-3585

CVSS v3

Risk Factor: Low

Base Score: 3.7

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

Vulnerability Information

CPE: cpe:/o:cisco:adaptive_security_appliance_software:9, cpe:/o:cisco:firepower_threat_defense:6

Required KB Items: Tenable.ot/Cisco

Patch Publication Date: 10/21/2020

Vulnerability Publication Date: 10/21/2020

Reference Information

CVE: CVE-2020-3585

CWE: 203

Detections

Analytics