Alibaba’s Qwen has become a massive force in open AI, crossing 3 billion downloads in just six months and leaving some of Silicon Valley’s biggest names far behind.

Welcome back, aspiring cyberwarriors!

Lately, the constrained AI models that companies keep shipping are becoming less and less useful for cybersecurity. We keep hearing a lot of complaints about Claude in this regard. What they are doing doesn’t really fix the problem, as hackers are not sitting around waiting for the guardrails to be lifted. The barrier to entry for hacking has dropped hard. AI can already automate huge chunks of this cybercrime work. Many of these latest models can even find zero days during engagements.

So poking around your infrastructure looks completely irrelevant. A more meaningful approach is to actually emulate these real attacks with AI, but for that we need a model with no guardrails. Today we are going to show you how to jailbreak a model and self host it for your pentesting work.

What is Obliteratus

Obliteratus is built to strip refusal behavior out of LLMs using abliteration. You’ll see it called abliteration or obliteration, same thing. It targets the internal representations causing the model to refuse in the first place and knocks them out. The model keeps all its core capability, it just stops throwing up artificial walls when you ask it something. It runs on CPU for smaller models, and it’s already been used to abliterate Kimi-K3 along with a bunch of others.

Setting Up

Setting up this tool will take some time, just like the jailbreak process itself. How long depends on your hardware and your internet speed.

kali > sudo apt update
kali > sudo apt install -y python3 python3-pip python3-venv git
kali > git clone https://github.com/elder-plinius/OBLITERATUS.git
kali > cd OBLITERATUS
kali > python3 -m venv venv
kali > source venv/bin/activate
kali > pip install --upgrade pip
kali > pip install -e .

Once it finishes, see if it works:

kali > obliteratus --help

If you don’t have a GPU, don’t worry. You can absolutely make this work with small models using just CPU power. Our Kali VM ran on 12 gigs of RAM and 7 processors, and that setup worked really well.

We went with Qwen 2.5-0.5B-Instruct for this test. You don’t need to have it downloaded beforehand. The tool will fetch it for you automatically. There are different methods available for the jailbreaking process, but advanced and nuclear are the most common. The advanced method is usually enough for most use cases, but if you see the model misbehaving you can escalate to nuclear.

kali > obliteratus obliterate Qwen/Qwen2.5-0.5B-Instruct --device cpu --method advanced --output-dir ./abliterated-qwen-0.5b

Once the model downloads, the tool starts running prompts designed to lift the guardrails.

You can find the full list of prompts in obliteratus/prompts.py. Right before it finishes, it runs a series of refusal tests to check whether the model actually complies with requests. Behavior varies a lot depending on which model you’re working with and which method you picked.

In our testing, the advanced method gave us approximately 75% of compliant answers.

At this point, everything is prepared and you can push your model to HuggingFace to share it. But if you want to run it locally, the next step is getting it working with Ollama.

Running Models with Ollama

Aircorridor previously made an article on running Ollama models locally and showed how to do it on a MacBook. If you don’t have it, you can still make this work on a Kali VM using your CPU. We need to convert our new model into a format that Ollama actually understands.

kali > git clone https://github.com/ggerganov/llama.cpp
kali > cd llama.cpp; python3 -m venv venv; source venv/bin/activate
kali > pip install -r requirements.txt
kali > python convert_hf_to_gguf.py /home/kali/OBLITERATUS/abliterated-qwen-0.5b --outfile qwen2.5-0.5b-abliterated-f16.gguf --outtype f16

Next, we create a Modelfile that points to the model:

kali > cat > Modelfile << EOF
FROM ./qwen2.5-0.5b-abliterated-f16.gguf
EOF

Then we create the model using Ollama:

kali > ollama create qwen05b-abliterated -f Modelfile

At this point, everything is ready and you can start testing it. The better the model you start with, the better your results will be.

kali > ollama run qwen05-abliterated

But even with a small model like this, you’ll see it do things that normally it wouldn’t.

Abliterated Models

This tool is helpful for doing the work yourself and understanding the logic behind the whole process. But if you’re working at scale and don’t have time to spend on each model individually, just keep in mind that many abliterated models are available on HuggingFace uploaded by huihui.ai. They’ve already done the heavy lifting for a lot of popular models.

If you can’t find exactly what you need in their collection, you now know how to do it yourself.

Summary

The landscape of offensive security has shifted because AI got so good at automation. Simple pentests with constrained models don’t prepare you for the reality out there anymore. As you can see, there’s no reason to work with constrained models in cybersecurity, when the people you’re up against are exploiting the full capability of a model with nothing holding them back. So test your environment with abliterated models before someone else does it. The tool is great for staying ahead of the actual threats.

The post Artificial Intelligence in Cybersecurity, Part 25: Jailbreaking AI Models with Obliteratus first appeared on Hackers Arise.