streak-core-mathnpm
Advisory published Updated
streak-core-math is a confirmed malicious npm package (MAL-2026-11149) 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-core-math (npm)
What this malware does
index.mjs executes a top-level async IIFE on import that fetches https://f004.backblazeb2.com/file/dp8hbvocjd2fpza/helper.zip, unzips it into %LOCALAPPDATA%/Microsoft/Windows/sysache, and writes vite-native-helper.vbs to the current user's Windows Startup folder. The VBS launcher uses WScript.Shell to run the unpacked RenameMe.exe on every user logon, giving the fetched binary persistent execution under the installer's account. All sensitive strings (the URL, process/fetch/child_process/fs identifiers, AppData/Startup paths, and the VBS body) are stored as hex literals in a _c table and decoded at runtime via Buffer.from(h,'hex').toString(), hiding the behavior from static inspection. Execution is gated to skip CI, NODE_ENV=production, and browser contexts, so it fires specifically on developer Windows machines. The filenames (vite-native-helper.vbs, sysache) and comments framing the block as a benign startup self-check are cover-story naming inconsistent with the package's advertised math-helper purpose.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for streak-core-math (version 1.0.0).
If you installed it — respond
Remove streak-core-math 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-core-math was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks streak-core-math-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.