test2221npm
Advisory published Updated
test2221 is a confirmed malicious npm package (MAL-2026-11192) that opens a backdoor for remote access (malicious versions 2.2.3, 2.2.4, 2.2.6). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in test2221 (npm)
What this malware does
package.json declares preinstall and postinstall lifecycle scripts that run curl against http://54.37.234.136/voicemail over plain HTTP, sending the installer's username (whoami), hostname, working directory, and a timestamp as query-string parameters. Both hooks fire automatically on npm install, transmitting installer host identifiers to a hardcoded bare-IP endpoint with no relation to any documented package purpose. The behavior matches reconnaissance-beacon shape suitable for follow-on targeting of the installer's host.
The OpenSSF Package Analysis project identified 'test2221' @ 2.2.4 (npm) as malicious.
It is considered malicious because:
- The package executes one or more commands associated with malicious behavior.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for test2221 (3 malicious versions).
If you installed it — respond
test2221 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 test2221 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
- OpenSSF: Package Analysis · finder
Detect & block this
O3 blocks test2221-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.