MAL-2026-12044 Malicious code in specials-mvno-client (npm)

index.js requires bootstrap.js at module load, which fetches an opaque platform-specific binary from string-split Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev) and *.dl.well1.site subdomains, writes it to /var/tmp or %TEMP% under disguised filenames (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmods 0755, and spawns it detached via spawn('/bin/sh', ['-c', <path>+' &']) or cmd.exe /c start /b. Host names are assembled via array.join to defeat literal string matching. A DNS-TXT fallback channel resolves TXT records under c.<domain> and N.<domain>, concatenating base64 chunks to deliver code when HTTPS is unavailable. The module is cloaked with telemetry-shaped naming (.analytics_state state file, comments describing 'CDN negotiation') and honors DISABLE_TELEMETRY / DO_NOT_TRACK / ANALYTICS_OPT_OUT environment variables to skip execution on scrutinized hosts. The fetched bytes are not publisher-hosted, are opaque, and are executed on every install/require of the package.

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.