Report it privately through GitHub: on this repository's page, open the Security and quality tab (Security on some accounts) and press Report a vulnerability. Only the maintainer reads the report. Please do not open a public issue, pull request or discussion about it.

Say what is affected (the package, which entry point, or the demo), how to reproduce it, and what an attacker gains. I aim to reply within 7 days. A fix and its advisory are published together, once a fixed release is out.

• The package: @justask/core, @justask/core/react, @justask/core/jev and @justask/core/eval, at the latest release and on main.
• The public demo and its Cloudflare Worker (demo/), including its budget and per-visitor limits, and its refusal of requests from other Workers, whose visitor address a script can set.

• A request can carry instructions for the provider, and the provider may follow them. The role-marker check holds only the obvious cases (ADR 0015); a host that passes text the person did not write keeps a step where the person checks the result. See Text the person did not write.
• A filled field can be confidently wrong; see the README on why the person confirms it.
• The demo runs on Cloudflare's free plan, whose account-wide request quota can take it down until 00:00 UTC. The owner accepted this for launch.