The npm package streak-math-kit version 1.0.0 contains malicious code that targets Windows Subsystem for Linux (WSL) developer environments. When imported, it drops a hidden Windows executable named vite-native-helper.exe into the Windows startup folder of a detected user profile, causing persistent execution on every Windows logon. The malicious behavior is obfuscated by hex-encoding path segments and the executable binary. This results in a persistent backdoor on Windows systems accessed via WSL.