Hands Off: Detecting Model Weight Tampering

Darek Stojaczyk, Rafael Tinoco | Stealthium | October 18, 2026

This article introduces Rank-One Model Editing (ROME) attacks, where a malicious Python module rewrites a model's weights in GPU memory to corrupt its answers, and explains why CPU-focused security tooling misses this class of attack. We then run a ROME attack in our lab and show how Stealthium detects model tampering via our runtime sensor, which ties every CUDA kernel launch back to the Python code that issued it, and new on-going research that detects the weight changes together with the call stack that caused it.

Models can be corrupted about a specific topic without a single byte on disk changing. There is nothing to scan, no process to catch, no signature to hunt and match. For everything and everyone watching the machine, it’s a model doing model things.