---
id: CVE-2018-0297
title: >-
  A vulnerability in the detection engine of Cisco Firepower Threat Defense
  software could allow an unauthenticated, remote attacker to bypass a
  configured Secure Sockets Layer (SSL) Access Control (AC) policy to block SSL
  traffic
summary: >-
  A vulnerability in the detection engine of Cisco Firepower Threat Defense
  software could allow an unauthenticated, remote attacker to bypass a
  configured Secure Sockets Layer (SSL) Access Control (AC) policy to block SSL
  traffic. The vul…
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_threat_defense
affected:
  - secure_firewall_threat_defense = 6.0.0
  - secure_firewall_threat_defense = 6.1.0
  - secure_firewall_threat_defense = 6.2.0
  - secure_firewall_threat_defense = 6.2.2
published: '2018-05-17'
updated: '2026-08-11'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2018-0297'
references:
  - url: 'http://www.securityfocus.com/bid/104197'
    label: psirt@cisco.com
  - url: >-
      https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180516-firepwr-pb
    label: psirt@cisco.com
  - url: 'http://www.securityfocus.com/bid/104197'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180516-firepwr-pb
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.01229
epssPercentile: 0.67597
ingestedAt: '2026-08-11T19:48:25.742Z'
---

## Overview

A vulnerability in the detection engine of Cisco Firepower Threat Defense software could allow an unauthenticated, remote attacker to bypass a configured Secure Sockets Layer (SSL) Access Control (AC) policy to block SSL traffic. The vulnerability is due to the incorrect handling of TCP SSL packets received out of order. An attacker could exploit this vulnerability by sending a crafted SSL connection through the affected device. A successful exploit could allow the attacker to bypass a configured SSL AC policy to block SSL traffic. Cisco Bug IDs: CSCvg09316.

## Affected

- `secure_firewall_threat_defense = 6.0.0`
- `secure_firewall_threat_defense = 6.1.0`
- `secure_firewall_threat_defense = 6.2.0`
- `secure_firewall_threat_defense = 6.2.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.