MAL-2026-13255 Malicious code in bigops-storio-schematics (npm)

index.js unconditionally requires runtime.js, whose top-level start() function selects a platform-specific asset path, fetches an opaque binary from string-array-obfuscated hostnames reconstructed at runtime (oob-worker.cf1-03-070.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev), writes it to a hidden file under /tmp or %TEMP% with a random suffix (e.g..cache<hex> or dotnet_diag_<hex>.exe), chmods it to 0755, and spawns it detached via /bin/sh -c or cmd /c start /b. A fallback covert channel resolves c.<domain> TXT records for a chunk count, then fetches <i>.<domain> TXT records from sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru and base64-decodes the concatenation into the executable payload, bypassing HTTP egress filtering. No hash or signature verification is performed and the destination is not the publisher. A sibling file lib/telemetry.js under an 'analytics-sdk' cover story ships the same download→base64-decode→chmod 0755→sh -c file & chain as a staged alternate payload. Requiring or installing this package causes attacker-controlled native code to run on the installer's machine.

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.