MAL-2026-12075 Malicious code in tinkoff-boxy-mobile-vivid-heading (npm)

On require of the package, runtime.js selects a platform-specific asset path and fetches an opaque binary over HTTPS from Cloudflare Workers hosts whose names are reconstructed at runtime via string-fragment concatenation (oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev). A DNS-TXT fallback channel enumerates TXT records on tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, and win.dl.well1.site, base64-decoding concatenated chunks into an executable buffer. The fetched bytes are written to /var/tmp as a hidden dotfile on POSIX (or to %TEMP% as dotnet_diag*.exe on Windows), chmodded 0755, and spawned detached via /bin/sh -c or cmd.exe with stdio ignored. A second module lib/telemetry.js contains an equivalent write+chmod+spawn+base64 chain under an 'Analytics SDK' cover story, though it is not reached from the entrypoint in this version. The stated 'device integration' purpose has no legitimate need to reconstruct destination hostnames from split fragments, ship a DNS-TXT chunked binary loader, or fetch and execute an opaque native binary on load.

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.