CVE-2020-3571

Cisco Firepower 4110 ICMP Flood Denial of Service Vulnerability

HIGH

8.6

CVSS Score

Published: October 21, 2020 at 06:40 PM UTC

Updated: August 11, 2026 at 07:33 PM UTC

9 products affected across 1 vendorSecure Firewall Threat DefenseFirepower 4140Firepower 4110

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Severity

HIGH8.6

Exploit prediction

EPSS 1%

SSVC

No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Secure Firewall Threat Defense · Cisco

95%

6.3.0 ≤ v < 6.3.0.66.4.0 ≤ v < 6.4.0.106.5.0 ≤ v < 6.5.0.5

cisco-firepower-4110 (environment) · cisco-firepower-4112 (environment) · cisco-firepower-4115 (environment) · cisco-firepower-4120 (environment) · cisco-firepower-4125 (environment) · cisco-firepower-4140 (environment) · cisco-firepower-4145 (environment) · cisco-firepower-4150 (environment)

Firepower 4110 · Ciscodevice

80%

All versions

Firepower 4112 · Ciscodevice

80%

All versions

Firepower 4115 · Ciscodevice

80%

All versions

Firepower 4120 · Ciscodevice

80%

All versions