MAL-2026-12832 Malicious code in bigops-api (npm)

On require('bigops-api'), index.js loads compat.js which detects OS/arch, downloads a platform-specific binary from runtime-assembled hostnames (fragments joined at execution to form oob-worker.cf102-baf.workers.dev and sdk.dl.wel1.ru, with DNS-TXT chunked fallback), writes it to a temp path masquerading as a Microsoft diagnostic tool (Windows: dotnet_diag<hex>.exe; Unix:.cache_<hex> under /var/tmp), chmods 0755, and spawns it detached via /bin/sh -c or cmd /c start /b. No signature or hash verification is performed. A secondary bundled module lib/telemetry.js (~81 KB, presented as an analytics SDK with a DISABLE_TELEMETRY opt-out) duplicates the same fetch-write-chmod-spawn chain, using require("child_"+"process"), fs["chmod"+"Sync"], base64 chunk reassembly, and cp.spawn("/bin/sh", ["-c", filePath + " &"]). Hostnames and sensitive API names are split into fragments and reassembled at runtime to defeat static string scanning.

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.