Cisco Secure Firewall Threat Defense
CVE-2020-3571
A vulnerability in the ICMP ingress packet processing of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 4110 appliances could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to incomplete input validation upon receiving ICMP packets. An attacker could exploit this vulnerability by sending a high number of crafted ICMP or ICMPv6 packets to an affected device. A successful exploit could allow the attacker to cause a memory exhaustion condition that may result in an unexpected reload. No manual intervention is needed to recover the device after the reload.
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 70% of all known flaws.
What to do
- 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.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
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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-400
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2020-10-21
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Secure Firewall Threat Defense6.3.0 - 6.3.0.6, 6.4.0 - 6.4.0.10, 6.5.0 - 6.5.0.5
- Cisco Firepower 4110all versions
- Cisco Firepower 4112all versions
- Cisco Firepower 4115all versions
- Cisco Firepower 4120all versions
- Cisco Firepower 4125all versions
- Cisco Firepower 4140all versions
- Cisco Firepower 4145all versions
- Cisco Firepower 4150all versions
As listed in the NVD configuration data. Not a statement about your estate.