---
id: CVE-2019-1970
title: >-
  A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security
  (TLS) protocol inspection engine of Cisco Firepower Threat Defense (FTD)
  Software could allow an unauthenticated, remote attacker to bypass the
  configured file po…
summary: >-
  A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security
  (TLS) protocol inspection engine of Cisco Firepower Threat Defense (FTD)
  Software could allow an unauthenticated, remote attacker to bypass the
  configured file po…
severity: medium
cvss: 5.8
cvssVector: 'CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N'
cwe:
  - CWE-693
  - CWE-693
vendor: cisco
product: secure_firewall_management_center
affected:
  - secure_firewall_management_center = 6.3.0
  - secure_firewall_management_center = 6.4.0
  - secure_firewall_threat_defense < 6.4.1
patched:
  - secure_firewall_threat_defense 6.4.1
published: '2019-08-08'
updated: '2026-08-11'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2019-1970'
references:
  - url: >-
      https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-ftd-bypass
    label: psirt@cisco.com
  - url: >-
      https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-ftd-bypass
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.01493
epssPercentile: 0.72586
ingestedAt: '2026-08-11T19:48:26.746Z'
---

## Overview

A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) protocol inspection engine of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the configured file policies on an affected system. The vulnerability is due to errors when handling specific SSL/TLS messages. An attacker could exploit this vulnerability by sending crafted HTTP packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured file policies and deliver a malicious payload to the protected network.

## Affected

- `secure_firewall_management_center = 6.3.0`
- `secure_firewall_management_center = 6.4.0`
- `secure_firewall_threat_defense < 6.4.1`

## Remediation

Upgrade past the affected range:

- `secure_firewall_threat_defense 6.4.1`