MAL-2026-12852 Malicious code in bigops-umf-statist (npm)

On require('bigops-umf-statist'), index.js loads runtime.js which selects a platform-specific endpoint, downloads a binary over HTTPS from string-obfuscated Cloudflare Workers hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf102-baf.workers.dev) with a DNS-TXT fallback channel that reassembles a base64 payload from TXT records under sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched bytes are written to /var/tmp or %TEMP% under a masquerading name (dotnet_diag<hex>.exe or.cache_<hex>), chmod 0755, and spawned detached via cmd.exe or /bin/sh. Destination hostnames are reconstructed at runtime by array-join to evade static inspection, and no signature or hash verification is performed on the downloaded 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.