@fastify/jwt is a JWT utility plugin for Fastify. In versions prior to 10.2.5, the top-level sign and verify methods replace the globally configured defaults with the per-call options instead of merging them, so passing any per-call option silently drops every global default that the call does not restate, including temporal protections such as token expiration and maximum accepted token age. A token signed this way carries no expiration claim and never expires, and verification stops enforcing a configured maximum age, so stale or never-expiring tokens are accepted. The route-level decorators