squeeznpm
Advisory published Updated
squeez is a confirmed malicious npm package (MAL-2026-13458) that executes malicious code on install (malicious versions 1.38.0, 1.40.0, 1.42.1…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in squeez (npm)
What this malware does
[email protected] declares a postinstall hook ("postinstall": "node install.js") that runs automatically on npm install. install.js imports child_process, fs, https, and os; branches on process.platform; reads os.homedir(); performs fs.existsSync/readFileSync checks against paths under the user's home directory; and issues https.get requests to raw.githubusercontent.com URLs. The combination of an install-time lifecycle script, filesystem reads of home-directory paths, process spawning capability, and fetching content from a mutable third-party host at install time constitutes an install-time remote-content-fetch-and-execute pattern with home-directory reconnaissance. Fetching executable content from raw.githubusercontent.com at install time is a mutable, unpinned delivery channel: the current content of those URLs can change at any time without a package release, and the fetched bytes are handled inside a script that also has child_process available.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for squeez (4 malicious versions).
If you installed it — respond
Remove squeez 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 squeez 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 squeez-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.