MAL-2026-16347

radio-player-theme presents itself as a radio player theme. The published tarball contains three files: package.json, style.css (declared as main) and payload.js, which holds the package's only executable code.

payload.js is a browser payload. On execution it reads location.origin and document.cookie, extracts the value of a MANAGER-XSRF-TOKEN cookie, and sends the origin together with the collected state to an out-of-band callback domain under oastify.com by assigning it to an Image.src. It then issues a second authenticated request to a third-party manager API and writes the collected data to window.__radioXssProof.

The file carries a comment describing itself as a bug bounty proof of concept for a CSP bypass through a public CDN that serves npm packages. Regardless of that claim, the published package delivers working data-collection code to anyone who loads it, and the package has no other function.

The package declares no install hooks, so npm install alone does not execute the payload; the code runs when the file is loaded in a browser, which is what CDN delivery of an npm package enables.

Evidence: payload.js:7 holds the hardcoded callback domain; payload.js:13-19 perform the cookie read and the beacons. Determination: manual review of the published tarball (sha256 ddbb93aa9416c1c89cf15dc7627f4a816a1c31929238ed8608264546ba0df186).