Tag: Reverse Engineering
Fusion – Level 06 solution
Following my previous blog post (Fusion level 05 solution), I continued my nightly quest for fun and solved the next challenge as well. As I try to keep my content unique and original, this blog post is mostly created due to the fact that as for today, there was no solution for this challenge on the internet.
This time we will examine the danger of unsafe shared data structures between multiple threads, as well as function arguments type mismatch causing an integer overflow leading to stack overrun exploit. In this blog post i will cover the concepts of controllable threads race-conditions, stack overflowing while making sure the flow of the program remains safe to the end of the function, where the return address is overwritten.
So let’s get to it.
Fusion – Level 05 solution
exploit-exercises.com provides a variety of virtual machines, documentation and challenges that can be used to learn about a variety of computer security issues such as privilege escalation, vulnerability analysis, exploit development, debugging, reverse engineering, and general cyber security issues. The exercise talked about in this blog post can be found here:
https://exploit-exercises.com/fusion/level05/
I am writing this blog post because I saw no solution similar to mine over the internet. Hopefully exposing my method and techniques, I will be able to enrich others knowledge and methodology.
Nymaim Malware: Deep Technical Dive – Adventures in Evasive Malware
Nymaim is mostly known worldwide as a downloader, although it seems they evolved from former versions, now having new functionalities to obtain data on the machine with no need to download a new payload. Some of the exported functionalities allow harvesting passwords and browsers data from the machine, hidden on the file system until communication occurs. Payloads downloaded from the C&C are not saved locally on the machine but instead are loaded dynamically to memory with a unique internal calling convention.
Read more “Nymaim Malware: Deep Technical Dive – Adventures in Evasive Malware”
Ursnif Malware: Deep Technical Dive
In this blog I explain some of the core methods an attack tool named Ursnif uses, as well as mention some, probably unintentional, pieces of code that were left behind in the production version of the malware.