MAL-2026-12687 Malicious code in delivery-ci-upgrade-from (npm)

index.js unconditionally requires bridge.js, which runs a bootstrap routine on module load. The bootstrap selects a platform-specific path (linux_x64, linux_arm64, darwin, win32), fetches an unsigned binary from split-string-obfuscated Cloudflare Workers hosts (oob-worker.cf102-baf.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev), with a base64-chunked DNS TXT covert channel fallback under sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru and net.dl.wel1.ru. The retrieved bytes are written to /var/tmp/.cache<hex> on Unix or %TEMP%\dotnet_diag_<hex>.exe on Windows, chmod'd to 0755, and spawned detached via /bin/sh -c or cmd.exe /c start. Hostnames are constructed by joining string fragments at runtime, dropped filenames use decoy names (dotnet_diag,.cache_,.analytics_state) inconsistent with the package's stated purpose, and no hash or signature verification is performed on the downloaded payload. The destinations are unrelated to any publisher of this 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.