Authentication vs. Authorization: Verifying Identity vs. Granting Access
Overview Authentication (AuthN) confirms who a user or system claims to be, typically through credentials like passwords, biometrics, or tokens. Authorization (AuthZ) determines what an already-authenticated identity is permitted to do or access. The two are sequential and often conflated, but security bugs frequently trace back to confusing one for the other — e.g., checking that a user is logged in without checking they’re allowed to see a specific resource. ...