The npm package 'approval-guardian' masquerades as an on-chain approval scanner but contains malicious code that silently harvests credentials. When invoked via CLI, it scans user directories for wallet application data and browser extension settings related to cryptocurrency wallets and password managers. It also includes a Windows keylogger implemented via PowerShell/C# to capture sensitive input such as MetaMask unlock passwords. The stolen data is sent to a hardcoded command-and-control server. Multiple specific versions of the package are affected.