6.7Medium

Cisco Secure Firewall Threat Defense

CVE-2020-3253

A vulnerability in the support tunnel feature of Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to access the shell of an affected device even though expert mode is disabled. The vulnerability is due to improper configuration of the support tunnel feature. An attacker could exploit this vulnerability by enabling the support tunnel, setting a key, and deriving the tunnel password. A successful exploit could allow the attacker to run any system command with root access on an affected device.

What this means for your business

  • It affects Cisco Secure Firewall Threat Defense. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it only with access to the machine itself, with an administrator login, and without anyone at your company clicking anything.

What to do

  1. 1Check whether your company or your suppliers run Cisco Secure Firewall Threat Defense, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
6.7 (v3.1)
Vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-284
Assigned by
psirt@cisco.com

Dates

Published
2020-05-06
Last modified
2026-08-11
Sources
NVD

Affected products

  • Cisco Secure Firewall Threat Defense- 6.5.0

As listed in the NVD configuration data. Not a statement about your estate.

References