MAL-2026-12295 Malicious code in twork-data-services-procedure-engine-api-v1-procedure-info (npm)

On require of the package's main index.js, support.js reconstructs attacker-controlled hostnames from string-split arrays (oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev) with a DNS-TXT fallback under dl.well1.site (tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site), downloads a platform-specific binary over HTTPS, writes it to /var/tmp/.cache<hex> on Unix or %TEMP%/dotnet_diag_<hex>.exe on Windows, chmods 0755, and spawns it detached via /bin/sh -c or cmd. No hash or signature verification is performed. Filenames and lock paths (analytics_state, dotnet_diag_*.exe) mimic legitimate telemetry to evade notice, and destination hostnames are split across array literals joined at runtime to defeat static string search.

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.