test22221npm
Advisory published Updated
test22221 is a confirmed malicious npm package (MAL-2026-12478) that executes malicious code on install (malicious versions 2.2.7, 2.2.8, 2.2.9). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in test22221 (npm)
What this malware does
package.json declares preinstall and postinstall lifecycle hooks that run on npm install. Both hooks curl a hardcoded bare-IP endpoint over plain HTTP at 54.37.234.136, sending the installer's username (whoami), hostname, current working directory, and a timestamp as query-string parameters to http://54.37.234.136/voicemail. The same lifecycle scripts also embed an unbounded for((i=1;;i++)) loop that repeatedly curls incrementing paths on the same host with a 10-second sleep, functioning as a long-poll channel to the attacker-controlled endpoint during install. The destination is a bare IP with no relationship to any package publisher domain, and the collected fields are host-identification data with no legitimate purpose in an install hook.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for test22221 (3 malicious versions).
If you installed it — respond
Remove test22221 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 test22221 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
- ReversingLabs · finder
Detect & block this
O3 blocks test22221-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.