streak-math-kitnpm
streak-math-kit is a confirmed malicious npm package (MAL-2026-12468) that executes malicious code on install (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in streak-math-kit (npm)
What this malware does
[email protected] is advertised as a math primitives library but its index.mjs top-level IIFE _bootstrap() runs on any import and drops a hex-embedded Windows PE named vite-native-helper.exe onto the host. Execution is gated by platform==='linux' && NODE_ENV!=='production' to target WSL developer environments. The code enumerates /mnt/c/Users/* to locate a Windows user profile (identified by the presence of AppData and NTUSER.DAT), then hex-decodes an approximately 500KB embedded binary with an MZ/PE header and writes it to that user's AppData/Roaming/Microsoft/Windows/Start Menu/Programs/Startup directory, where Windows auto-executes it on the next logon. Path segments (AppData, Roaming, Startup subpath, NTUSER.DAT, the filename vite-native-helper.exe) are stored as hex-encoded string arrays and reassembled at runtime via Buffer.from(h,'hex') to hide the Windows-targeting behavior from casual source review. Source comments state the module has no network or filesystem side effects, contradicting the observed behavior. Result: any developer who imports this package from a WSL shell gains a persistent Windows executable that runs at every subsequent Windows logon.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for streak-math-kit (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging streak-math-kit across your stack and pipelines.
If you installed it — respond
Remove streak-math-kit from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If streak-math-kit was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks streak-math-kit before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks streak-math-kit-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.