CVE•Published 2020-10-21•Modified 2026-08-11•1 article on news•5 live references•NVD data

CVE-2020-3571Cisco · Secure_firewall_threat_defense

Vulnerability data via NVD (ingested)

CVSS v3.1

8.6

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS percentile

Exploit Prediction Scoring System · top 31% of all CVEs

Weaknesses (CWE)

CWE-400Uncontrolled Resource Consumption CWE-20Improper Input Validation

Description

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.

Timeline

Published 2020-10-21

Modified 2026-08-11

External references

NVD MITRE Exploit-DB GitHub PoC VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2020-3571

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Cisco Secure Firewall Threat Defense"

All exposed Cisco Secure Firewall Threat Defense instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Secure Firewall Threat Defense"

HTTP body or banner mentions "Secure Firewall Threat Defense" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2020-3571