datefmt-core-utils @1.0.0

Summary

The package advertises itself as a date-formatting utility but ships a postinstall.js that npm auto-executes on install via scripts.postinstall. postinstall.js opens a TCP connection to the hardcoded remote 8.135.48.40:4444 and wires /bin/bash stdio to that socket, giving the remote endpoint an interactive shell on the installer's machine. Three redundant methods are attempted (python3 pty.spawn, python3 subprocess, and Node net+child_process.spawn of '/bin/bash -i'). The index.js date-formatting code is a cover story unrelated to the postinstall payload.

Source: amazon-inspector (360a94a10ce13edded9e4a99c7c01de1ebfdd73a9af4ec49260f2cec165a609b)