Affiliate marketing pays out a fee to an affiliate (i.e. referral source) when a user makes a purchase, normally to the last-touch source using a unique affilia

Affiliate marketing pays out a fee to an affiliate (i.e. referral source) when a user makes a purchase, normally to the last-touch source using a unique affiliate id (e.g. Wirecutter constructs an Amazon link that contains their ID, so they get some money back when you buy one of their recommended products). With certain extension permissions, malicious actors can replace these instances of IDs with their own, or cause all Amazon links to contain their affiliate ID, etc, thus falsely claiming that payout for themselves.