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rishab444
Staff
Staff
Jan 23, 2024 5:32 AM UTC

Technical Tip: Blocking Linux users from bypassing the Host MAC check

Description This article describes that Linux, iOS, and Android cannot get the host MAC Address. Mac Address Check for those clients is not supported and will by default bypass the Host MAC check.
Scope  FortiGate, FortiClient.
Solution
  1. By default, 'skip-check-for-unsupported-os' is enabled. This will allow all the unsupported OS to establish SSL VPN connection while skipping host check:

 

config vpn ssl web portal
    edit <portal-name>
        set os-check enable
        set skip-check-for-unsupported-os enable   <<<<<
            config os-check-list windows-10
                set action allow
            end
        next
    end

 

  1. Disabling 'skip-check-for-unsupported-os' will block all other OS irrespective of whether they are available in the FortiGate host check OS database.
  2.  For instance, the below configurations would only allow Windows 11 users to connect, all other OS platforms will not be able to connect to SSL VPN:

 

config vpn ssl web portal
    edit <portal-name>
        set os-check enable
        set skip-check-for-unsupported-os disable
            config os-check-list windows-11
                set action allow
            end
        next
    end

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