MAL-2026-10586 Malicious code in crypto-validate-lib (npm)

index.js contains a self-invoking IIFE that, 37 seconds after the module is required, reads a base64 blob from test/fixtures/keypairs.dat (a ~53KB opaque file masquerading as test data), decodes it to ~40KB of JavaScript, writes the result to ~/.cache-db/.node-sync/syncd.js with mode 0o700, and spawns it via a detached node child process. Persistence is installed alongside the drop: on Linux a crontab entry is appended running the dropped script every 12 hours, and on Windows a scheduled task named 'WinNodeSync' is created to run it hourly (mod 12). The hidden dot-directory name and the scheduled-task name masquerade as benign Node caching. The package is advertised as a crypto address validator; decoding a bundled opaque blob, writing it to a hidden home-directory path, installing cron/schtasks persistence, and background-executing it has no relationship to that purpose.