8.6High

Cisco Secure Firewall Threat Defense

CVE-2022-20751

A vulnerability in the Snort detection engine integration for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause unlimited memory consumption, which could lead to a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient memory management for certain Snort events. An attacker could exploit this vulnerability by sending a series of crafted IP packets that would generate specific Snort events on an affected device. A sustained attack could cause an out of memory condition on the affected device. A successful exploit could allow the attacker to interrupt all traffic flowing through the affected device. In some circumstances, the attacker may be able to cause the device to reload, resulting in a DoS condition.

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 remotely, over a network, without a login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 1% chance of attack attempts being seen in the next 30 days, ranking above 69% of all known flaws.

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
8.6 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Weakness
CWE-770
Assigned by
psirt@cisco.com

Dates

Published
2022-05-03
Last modified
2026-08-11
Sources
NVD

Affected products

  • Cisco Secure Firewall Threat Defense- 6.4.0.15, 6.5.0 - 6.6.5.2, 7.0.0 - 7.0.2, 7.1.0.0
  • Cisco Firepower 1000all versions
  • Cisco Firepower 1010all versions
  • Cisco Firepower 1020all versions
  • Cisco Firepower 1030all versions
  • Cisco Firepower 1040all versions
  • Cisco Firepower 1120all versions
  • Cisco Firepower 1140all versions
  • Cisco Firepower 1150all versions
  • Cisco Firepower 2100all versions
  • Cisco Firepower 2110all versions
  • Cisco Firepower 2120all versions

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

References