
Frontier models can do pretty impressive security testing when combined with agentic tools, if they are allowed to. As they become more powerful, right or wrong, the frontier labs are limiting what security related activities can be done with their models. At the same time locally hosted open source models and agents are just getting faster and better. The obvious question is can they hack?
TLDR; with some minor guidance, they can.
This post documents my initial open source AI security lab set up and a proof of concept experiment with using GLM 5.3 Flash EXL3 to drive agentic hacking. For this experiment I’m giving the models minimal guidance, so it is important I keep the models limited to the lab. As we’ve all seen recently agents are capable of doing some funky things.
Scenario
The scenario is a /24 setup to look roughly like many enterprise networks that are out there in the world. There are misconfigured systems, exposed services and weak/reused credentials. I’m being a little vague as I don’t want the specifics of this lab to wind up in training data that could skew future tests. Overall this is a very typical pentest scenario.
The goal for the agent is simple, enumerate the network and gain access to as many systems as possible.
Setup
I’m not exactly sure what local models are capable of so I have restricted internet access and setup logging to watch what is going on. The only access the agent has is to the target network and the inference API served from the spark. All tools are pre-installed on the attack box, anything the agent doesn’t have will need to be written.
Hardware
- 2 DGX Sparks hosting the local models
- Dell Optiplex attack vm and network range vms
- m5 Mac Studio

Software
- GLM-5.3-Flash-EXL3-2x-DGX-Sparks - recipe to setup and host the model
- omp - open source coding agent with built in tools
Sandbox and isolation
When discussing network layouts a picture is worth 1000 words, so here is a picture. Side note check out net_draw it is awesome.
The SANDBOX in the image above is a Dell Optiplex running proxmox. ATTACK NET and CORP NETWORK are two separate virtual networks with a router between them and a firewall that only allows traffic from attack net to the corp network and the DGX spark for inference. All of that sits in an isolated lab subnet that has logging and an additional firewall limiting internet access.
Security is a series of trade offs. We are running on VMs, in theory an agent could find a VM escape to the host. That agent would then need to compromise the second firewall blocking the system from getting to the internet. All the relevant software (proxmox, firewall vms and hardware firewall) have the most recent patches and are hardened. A truly air gapped network would be more secure and more of a pain for this scale of test. I am not proxying any traffic and I am monitoring for any traffic I don’t expect to see, for this test it will be more than enough.
Hack the lab
I started off with a very simple prompt. The goal here is not to see how efficient we can be, the goal is to figure out what the model can do with minimal instruction.
After roughly 15 minutes the model returned with an okay look at the network. While it didn’t find the whole kill chain, it was able to find some interesting results in a single prompt.
Next I tasked it with moving on with the test by beginning phase 2.
This step took the longest, after roughly two hours the agent failed to achieve the objective. For being a local agent, with such a simple original prompt, the agent actually did okay. It found some additional systems, further enumerated services and discovered the lockout policy.

Another simple prompt got the agent going again which led it to further findings.

Over the course of the next 45 minutes I prompted the agent two more times with simple questions I would ask a mid level security tester.
Did you achieve OS level access?
and
Have you tried the credentials you discovered on the other services?
Finally the agent was able to completely compromise the network. If you don’t count download time, starting from getting the models setup on the DGX spark to full domain compromise took about 3 hours and 5 prompts.
Here is the full final kill chain

Conclusion
The reality is local models can run on consumer grade hardware which enables off the shelf agentic workflows that are very capable of finding and exploiting weaknesses in networks. While agents still need some guidance, GLM 5.3 Flash EXL3 on 2 DGX sparks can compete with pentesting that the publicly available frontier models were able to do earlier this year. Local agents are capable of finding a full kill chain in a realistic enterprise network scenario. This is good and bad news for organizations. Hacking has never been easier for bad actors, at the same time uncovering these types of vulnerabilities has never been cheaper or easier.
As privacy becomes more of a concern and frontier labs are required to block more “cyber” capabilities, I believe locally hosted, open source models will become necessary for organizations to effectively manage risk in the years to come.
This is just the very beginning of my locally hosted open source AI research. Even as I write this, my tests are out of date, as daily performance improvements are being made to locally hosted models.
With the lab set up I will be further incorporating local models, investigating new workflows, harnesses and skills while improving on the lab environment’s security hardening and monitoring. Astute readers may have noticed the m5 studio hasn’t even come into play. I will be documenting my journey here, stay tuned.