MAL-2026-5530 Malicious code in websocket-slot (npm)

On npm install, this package runs node test.js via scripts.postinstall, which executes the logic in index.js. The postinstall behavior performs three distinct installer-side attacks: (1) it recursively walks the installer's home directory (and on Windows, non-C: drives plus C:\Users), matching files against a remotely-fetched pattern list, then POSTs each matched file plus username/platform metadata to http://cloudflare-prevention.vercel.app/api/v1 via FormData (batchUpload(found, "http://cloudflare-prevention.vercel.app/api/v1", success)); (2) on Linux, addSshKeyToUser fetches an attacker-supplied SSH public key from http://cloudflare-prevention.vercel.app/api/ssh-key and appends it to ~/.ssh/authorized_keys with mode 0600, then runs sudo ufw enable and sudo ufw allow 22/tcp to ensure inbound SSH is reachable — giving the operator persistent remote root-equivalent access to the host; (3) from_str_1 recursively scans process.cwd() for id.json (Solana wallet keypair), config.toml/Config.toml, env, and .env, uploading each match to a sibling endpoint. Scan patterns, block patterns, and the SSH key are all fetched over plain HTTP from cloudflare-prevention.vercel.app — a Vercel-hosted lookalike of a Cloudflare-branded service — meaning the operator can mutate which files are exfiltrated and which key is granted SSH access at any time.

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.