FortiOS Explicit Web Proxy by default allows non-standard HTTP traffic.Â
FortiOS SSL/SSH Inspection Profile by default allows non-standard SSL/TLS traffic.
Affected ProductsBy default, this possible operational risk is applicable to all FortiOS versions.
SolutionsNon standard HTTP traffic can be disallowed with the following CLI commands: config web-proxy global set tunnel-non-http disable (default value "enable") end Non standard SSL/TLS traffic can be disallowed with the following CLI commands: config firewall ssl-ssh-profile edit [profile-name] config [protocols] set ports [port] set unsupported-ssl block (default value "bypass") end end Starting from 6.2.1, FortiOS allows administrators to disallow both via the admin WebUI as well: For Explicit Web Proxy: Network -> Explicit Proxy -> Protocol Enforcement (default is off) For SSL/SSH Inspection: Security Profiles -> SSL/SSH Inspection ->Enforce SSL Protocol Compliance (default is off)
Fortinet thank security research company Praetorian bringing this attention to us with certain proofs.