A channel accessible by non-endpoint vulnerability [CWE-300] in Fortinet FortiOS version 7.4.0 through 7.4.3, 7.2.0 through 7.2.7 and before 7.0.14 & FortiProxy version 7.4.0 through 7.4.3, 7.2.0 through 7.2.9 and before 7.0.16 allows an unauthenticated attacker with the knowledge of device specific data to spoof the identity of a downstream device of the security fabric via crafted TCP requests.