An invitation link is a URL that grants access to a specific session, resource, or group entry point. It is common in collaboration tools, private meetings, and shared web resources, where the link acts as a lightweight access credential instead of a username and password.
In cyber security, invitation links matter because they can behave like bearer tokens: anyone who has the link may be able to join, even if they were not the original recipient. Attackers exploit weak link handling through forwarding, replay, guessing, or reuse after expiration. Defenders reduce risk with short-lived links, single-use tokens, guest scoping, and visible host controls. A secure design does not just protect the traffic; it also controls who can enter, for how long, and what they can do once inside.