MAL-2026-12265 Malicious code in tinkoff-statist-browser-typed-client-jumptaxi.feature.contacts (npm)

The package's index.js unconditionally requires vendor.js on load, which runs a bootstrap routine that fetches a platform-specific binary over HTTPS from one of three Cloudflare Workers hosts whose hostnames are assembled by concatenating string fragments (oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev), with a DNS TXT fallback discovery channel using tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, and win.dl.well1.site. The fetched bytes are written to /var/tmp or %TEMP% under disguised names (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmod 0755, and detached-spawned via /bin/sh -c or cmd. No hash or signature verification is performed. lib/telemetry.js additionally loads child_process via require("child_" + "process") and calls fs["chmod"+"Sync"] to defeat static string matching. The fetched payload and destinations are unrelated to the declared 'contacts wrapper' purpose of the package.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.