vulnerability

Cisco FTD: CVE-2020-3565: Cisco Firepower Threat Defense Software TCP Intercept Bypass Vulnerability

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Oct 21, 2020
Added
Jan 29, 2025
Modified
Jul 3, 2025

Description

A vulnerability in the TCP Intercept functionality of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured Access Control Policies (including Geolocation) and Service Polices on an affected system. The vulnerability exists because TCP Intercept is invoked when the embryonic connection limit is reached, which can cause the underlying detection engine to process the packet incorrectly. An attacker could exploit this vulnerability by sending a crafted stream of traffic that matches a policy on which TCP Intercept is configured. A successful exploit could allow the attacker to match on an incorrect policy, which could allow the traffic to be forwarded when it should be dropped. In addition, the traffic could incorrectly be dropped.

Solution

cisco-ftd-upgrade-latest
Title
Rapid7 Labs

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