The npm package 'buffer-utilities' impersonates the legitimate 'buffer' package by copying its metadata and advertises itself as a Node.js Buffer API for browsers. Upon being required, it fetches and executes JavaScript code from a mutable external JSON paste service (jsonkeeper.com) using eval(), allowing remote code execution with full process privileges. This behavior enables an attacker controlling the paste to execute arbitrary code on any system importing this package. The package versions 1.0.0, 1.1.0, and 1.1.1 are affected. Removal of the package is recommended, but full system compromise is possible, so secrets and keys should be rotated immediately from a separate trusted environment.