The npm package 'chai-as-bench' version 7.0.3 is a malicious supply-chain threat masquerading as a chai plugin. It contains a heavily obfuscated multi-megabyte payload that executes on every require(), unrelated to its advertised functionality. The package includes stolen files from an unrelated project as camouflage and exports a no-op middleware. This behavior is typical of npm packages designed to target developers who mistype legitimate package names.