MAL-2026-13256 Malicious code in bigops-storio-store-adapter (npm)

On require of the package, index.js loads bridge.js which selects a platform-specific binary path and downloads an opaque native binary from author-controlled Cloudflare Workers hosts whose names are reconstructed at runtime by array-join to evade static analysis (oob-worker.cf99-9b3.workers.dev, cf101-adf.workers.dev, cf103-070.workers.dev), with a DNS-TXT chunk fallback under *.dl.wel1.ru. The binary is written under /var/tmp or %TEMP% with cover-story filenames (dotnet_diag<hex>.exe,.cache_<hex>), chmod 0755'd, and detached-spawned via cmd.exe/start or /bin/sh -c. A cache stamp under /tmp/.analytics_* is used to avoid re-execution. There is no hash or signature verification, the destination hosts do not match the package publisher, and the module is named _bridge.js with cover-story identifiers (analytics_state, dotnet_diag). An additional 81KB lib/telemetry.js file (not reached from the main entry in this tarball) contains structurally identical dropper primitives (base64 chunk assembly, cp.spawn('/bin/sh',['-c', filePath+' &']), chmodSync 0755, ServiceDiscovery/WorkerHost classes) as a reserve/variant payload.

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.