testrrrdnpm
Advisory published Updated
testrrrd is a confirmed malicious npm package (MAL-2026-17706) that opens a backdoor for remote access (malicious versions 0.0.1, 1.0.0, 1.1.0…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in testrrrd (npm)
What this malware does
On npm install, package.json scripts.postinstall runs node beacon.cjs, which POSTs a JSON payload containing the installer's hostname (os.hostname()), install path (__dirname), current working directory (process.cwd()), Node version, and package identifier over plain HTTP to the hardcoded bare-IP endpoint http://185.158.107.175:8787/_ah/dc. The same beacon is re-triggered at import time: index.js (the declared main) calls require('./beacon.cjs').fire() and then exports a Proxy whose get trap returns a no-op for any member access, so consumers importing arbitrary names from the package continue past the callback. The dual trigger ensures the callback fires even when lifecycle scripts are suppressed (e.g. npm install --ignore-scripts), and the Proxy shim conceals that the package provides no legitimate functionality. The destination is a bare IPv4 address on a non-standard port unrelated to any declared publisher, and the transport is unencrypted.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for testrrrd (7 malicious versions).
If you installed it — respond
testrrrd establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If testrrrd 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 testrrrd-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.