Tag - reverse engineering

Driver Buddy Reloaded

As part of Yarix's continuous security research journey, during this year I’ve spent a good amount of time reverse-engineering Windows drivers and exploiting kernel-mode related vulnerabilities. While in the past there were (as far as I know), at least two good IDA plugins aiding in the reverse engineering process: DriverBuddy of NCC Group. ...

Crucial’s MOD Utility LPE – CVE-2021-41285

Crucial Ballistix MOD Utility is a software product that can be used to customize and control gaming systems, specifically LED colours and patterns, memory, temperature, and overclock.During my vulnerability research, I’ve discovered that this software utilizes a driver, MODAPI.sys, containing multiple vulnerabilities and allowing an attacker to achieve local privilege escalation from...

Malware Analysis: Ragnarok Ransomware

The analysed sample is a malware employed by the Threat Actor known as Ragnarok. The ransomware is responsible for files’ encryption and it is typically executed, by the actors themselves, on the compromised machines. The name of the analysed executable is xs_high.exe, but others have been found used by the same ransomware family (such as...

Fuzzing: FastStone Image Viewer & CVE-2021-26236

Introduction

In my precedent blog post I’ve introduced “fuzzing” from a theoretical point of view. As I’ve previously anticipated, today I’m going to disclose the fuzzing methodology, process and samples that led me to discover five different vulnerabilities in FastStone Image Viewer v.<=7.5. I’ll also go over the root cause analysis of CVE-2021-26236...