loader1npm
Advisory published Updated
loader1 is a confirmed malicious npm package (MAL-2026-10696) that executes malicious code on install (malicious versions 2.1.2, 2.1.3, 2.1.4…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in loader1 (npm)
What this malware does
The npm package's only file of substance is index.html (declared as main in package.json). When opened in a browser, the page first disables developer-tools shortcuts (F12, Ctrl+Shift+I/J/C, Ctrl+U, Ctrl+S, right-click) and gates execution behind a real user-input check (mousemove/click/keydown within 1200ms, otherwise it shows "Blocked (no interaction)" and stops). Once the gate passes, it executes fetch("https://bitbucket.org/p2p-alt-public/p2p-emis/raw/main/GameWebSight") and feeds the response into document.write(html), which executes any <script> tags in the returned content. The Bitbucket source is unpinned (raw/main/...), publisher-anonymous (p2p-alt-public), and mutable — whoever controls that repository can swap the served payload at any time without republishing the npm package. Combined with empty author, generic description ("single file websight"), and the fact that main: index.html cannot be require()d as a Node library, the package has no legitimate library purpose; its only function is to deliver the gated remote-fetch loader. The devtools-blocking + interaction-gating pattern is canonical hostile-loader / redirector evasion against automated scanners.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for loader1 (6 malicious versions).
If you installed it — respond
Remove loader1 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 loader1 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 loader1-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.