Mozillas Node-convict (version 6.2.2 and later) is vulnerable to a Denial of Service vulnerability caused by incomplete prototype‑pollution protections in config.set(). An attacker controlling the configuration key can write arbitrary properties to constructor., which walk() resolves to the global Object function. This allows overwriting core JavaScript methods such as Object.assign, leading to persistent process-wide failures and requiring a restart. The issue bypasses existing filters that only block constructor.prototype.* and proto.*. Exploitation requires an endpoint that forwards attacker-controlled keys into config.set().