Technical Tip: Blocking Google Search AI mode via Web filter profile

Some organizations decide to block the AI Mode feature in the Google Search engine, and this can be accomplished using a web filter profile. Selecting AI Mode option of the Google Search triggers a URL with a parameter of ?udm=50 as part of the URL. The UDM in Google Search refers to Unified Delivery Mode, which is a parameter that controls how search results are displayed, and the number 50 triggers the AI mode feature of the Google Search. 

Go to Security Profiles -> Web Filter and edit the Web Filter profile that is assigned to the policy that the outgoing traffic towards the Google destination is matched with.  From 'Static URL Filter', enable 'URL filter' (if it has not been enabled already) and select 'Create New'. Configure the URL filter as follows:

• URL: *.google.com/*udm=50*.
• Type: Wildcard.
• Action: Block.
• Status: Enable.

The configuration on the CLI can be set up as follows:

config webfilter urlfilter
    edit 1
        set name <webfilter name> 
            config entries
                edit 1
                    set url *.google.com/*udm=50*
                    set type wildcard
                    set action block
                    set status enable
                next
            end
    next
end

Ensure that the Web Filter profile is actually applied to the correct Firewall Policy:

1. Go to Policy & Objects > Firewall Policy.

2. Identify the LAN -> WAN policy.

3. Verify that Web Filter is toggled ON and the specific profile is selected.

Note: To block Google Search AI mode (the ?udm=50 parameter) using the method described above, the user must enable HTTPS Deep Packet Inspection (SSL/SSH Inspection) in the firewall policy.