Security on kimobu

Vibe coding a Mach-o parser

Sun, 13 Apr 2025 00:00:00 +0000

Way back in 2021 when I was working on my dissertation I used a Python library called macholibre to parse Mach-O files. There are several other options for parsing these file types. I’m sure they’re all great, but it’s a lot to go through to find some features I want. Mainly, outputting as JSON to easily load into other applications. This seemed like a good opportunity to try vibe-coding a Swift-based Mach-O parser using ChatGPT. After some trial and error, I’ve made MachP available. Let’s look at how this went.

GPT Detections on Windows and Linux

Mon, 17 Feb 2025 00:00:00 +0000

Introduction

This is a follow up to A Little Less Malware, applying the same techniques to Linux and Windows data. There are some differences with this experiment. In the last one, we used Apple’s ESF to collect telemetry, which gave us process group identifiers to work with. In this experiment, I’m using only the Elastic Agent and the process telemetry it provides. Unfortunately, Elastic Agent does not send PGID for Linux, and while Windows notionally supports the concept, in practice it does not exist. First let’s look at a couple of ways to group activity without PGIDs.

A Little Less Malware a Little More Context: Using AI to detect malicious activity

Fri, 27 Dec 2024 00:00:00 +0000

Introduction

A coworker and I gave a talk at Objective by the Sea v7 on using Large Language Models (LLMs) as a behavioral detection. Another speaker, Colson, gave a great talk on why behavioral detections are so useful. LLMs are particularly adept at understanding and processing language-like structures, which include not only traditional text but also command-line arguments. In cybersecurity events, where command-line interactions often reveal attacker behaviors, LLMs can be leveraged to do behavioral detection without needing to be an expert in analyzing malicious actions or writing detections.

Adding macOS to my security homelab

Wed, 10 May 2023 00:00:00 +0000

This post has notes on how I added a macOS machine to my security homelab.

Install macOS to Proxmox

Follow this guide to install macOS onto a Proxmox cluster. This will result in an x86 based VM. I plan on looking into an ARM node in the future. Reference this page if you don’t want to extract OSK yourself. Additional note, this installed to local-lvm, not my GlusterFS storage.

Bind macOS to Active Directory

Since the rest of the lab is a Windows Active Directory domain, I wanted to join the macOS VM to the domain so domain users could login. Follow the guide here for high level guidance. Ventura changed the look of the Directory Utility but the overall concepts are the same. In Directory Utility, tick the option to “create mobile account at login” and add the “Users” OU to allowed administration.