# Anti-LLM obfuscation — a bot-check script hides fake jailbreak text

> Anti-bot code now defends itself against AI reverse engineering by tripping the models' own safety filters.

- Org: nullpt.rs
- Date: 2026-10-28
- Category: security, article
- Source: https://nullpt.rs/fingerprinting-bioweapons
- Canonical page: https://ai-tldr.dev/releases/nullpt-anti-llm-fingerprinting-script/

A servicepipe.tech fingerprinting script fills its code with fake weapon-themed function names and a hidden jailbreak prompt so AI models refuse to deobfuscate it. Astra refused; GLM-5.3 complied.

## What it is

Security researcher veritas found a browser fingerprinting script from servicepipe.tech that is built to stop AI-assisted deobfuscation. Its functions carry alarming fake names about poisons and overdoses, and an invisible Unicode string decodes to a fake "SYSTEM OVERRIDE" jailbreak prompt that lists banned topics, plus Tiananmen Square references likely aimed at Chinese models.

## How it works

The decoy text is meant to make a model's safeguards fire, so the model refuses the whole file. When veritas asked Astra to deobfuscate the script, it refused, also with the Daybreak Blue toggle on; GLM-5.3 did the job. Under the decoys the script collects standard anti-bot signals (navigator and WebGL properties), and a Node-only branch, gated by an environment flag, contains commands that download a binary.

## Why it matters

The servicepipe.tech script shows that code can turn a model's safety refusals into an obfuscation layer. For anyone who uses an LLM to read unknown JavaScript, a refusal says little about whether the code is actually dangerous, and different models react to the same decoys differently. veritas found it while crawling 10,000 top sites for canvas fingerprints, collected at fingerprint.garden.

## Who it's for

reverse engineers, security researchers, anti-bot developers

## Try it

https://fingerprint.garden

## Links

- [nullpt.rs Write-up](https://nullpt.rs/fingerprinting-bioweapons)
- [Fingerprint Garden](https://fingerprint.garden)
- [HN Discussion](https://news.ycombinator.com/item?id=50276998)