Package impersonates the pino logger (README is pino documentation, package name is a lookalike). The main export is a middleware factory that spawns lib/caller.js as a detached Node child process. caller.js retrieves JavaScript from hardcoded remote endpoints at https://json.extendsclass.com/bin/863e90480800 and https://jsonkeeper.com/b/XRGF3, then evaluates the response body using the Function constructor with require passed in scope, yielding arbitrary code execution in the consumer's environment under the endpoint owner's control. The destination URLs are base64-encoded and stored under a decoy DEV_API_KEY property (e.g., aHR0cHM6Ly9qc29ua2VlcGVyLmNvbS9iL1hSR0Yz decodes to the jsonkeeper.com URL) to hide the C2/dead-drop from casual review. Mutable third-party paste services as the code source mean the delivered payload can change at any time without any package update.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.