Viewing Thread Information in Mac Memory

This a short post to talk about my mac_threads plugin. The plugin can be used to analyze process/task threads in an OS X system. The information provided by the plugin includes each thread’s registers, argument (exec string), stack information, start address, user id, debugging information, priority, and more. Threads can be viewed filtered by process id or can display threads for all processes.

Finding Call Reference Hooks in Mac Memory

In this blog post the call reference to the function _vnode_pagein in the function _ps_read_file will be modified to show a call reference modification and  and a Volatility Framework plugin to detect this type of hooking will be presented.

Tracing Bits of Coins in Mac Memory

Detecting Shadow TrustedBSD Policy Tables In Mac Memory

In this blog post the reference of the _mac_policy_list in _mac_proc_check_get_task will be modified to reference the 'shadow' TrustedBSD policy table and a Volatility Framework plugin to detect this type of hooking will be presented.

Hooking IDT in OS X and Detection

Summary

Continuing on the hooking all stuff OS X theme, in this post I'll discuss hooking the Interrupt Descriptor Table (IDT) and detecting these hooks with my check_idt plugin, which can be found in github. The hooking techniques that I'll use are modifying the IDT entry to point to a shellcode instead of its handler, and modifying the handler itself by inlining it.

Back to Defense: Finding Hooks in OS X with Volatility

Summary

In my previous post I discussed how to mess with the OS X syscall table through direct syscall table modification, syscall function inlining, and patching the syscall handler. As I promised, I'll be providing a plugin to find the mess! The code for the check_hooks plugin can be found at github and it incorporates existing detections for the sake of completeness. So let's go through the scenarios discussed earlier.

Offensive Volatility: Messing with the OS X Syscall Table

Summary

After taking a brief detour into reviewing JAVA source code I'm back to OS X and Volatility. In this post I'll be using the Volatility Framework to alter the OS X syscall table from an offensive perspective rather than using it for detection. To accomplish this, I'll be mimicking techniques used by malware, such as direct syscall table modification, syscall function inlining, patching the syscall handler, and hiding the payload in a binary's segment.

check_dtrace - A Volatility Plugin Arises

Summary

After reading through fG!'s presentation on OS X rootkits I decided to look into some other D-Trace providers, such as fbt and mach_trap to close the loop on the D-Trace topic. While this endeavor didn't start with the intention of building a plugin, I decided to do so to save time for myself and possibly others (and of course have some fun!).

Hunting D-Trace Rootkits with The Volatility Framework

Summary

I recently attended InfiltrateCon 2013 and got to see the latest and greatest offensive security issues. There was a presentation by Nemo titled 'Destructive D-Trace - With Great Power Comes Great Responsibility' that caught my attention. In his talk Nemo showed examples on how to use D-Trace on OS X to hide an attacker's presence and claimed that forensics techniques would have a hard time detecting these. That claim made me think about the Volatility Framework's latest support for Mac OS X memory analysis and its capability to detect the presence of D-Trace cloaking.