A gatekeeper platform is a dominant service that controls access to users, traffic, or market reach. In cybersecurity, this can be a search engine, app store, identity provider, cloud marketplace, or other intermediary that decides what is visible, trusted, or allowed to connect. Because it sits between users and destinations, its ranking, filtering, and approval rules can shape who gets seen and who gets blocked.
This matters because control of a gatekeeper creates both opportunity and risk. Attackers may try to abuse the platform’s trust, manipulate rankings, hijack accounts, or exploit its moderation and distribution channels to reach large numbers of victims quickly. Defenders also depend on gatekeepers for access control, reputation checks, and fraud detection. When the gatekeeper is opaque or compromised, it can become a single point of failure that amplifies phishing, malware delivery, and visibility abuse.