When a user opens "22793.rar" (or similar ACE-based exploits):

The file is a well-known proof-of-concept (PoC) archive used to demonstrate a critical vulnerability in WinRAR (tracked as CVE-2018-20250 ).

No complex exploit was needed; the Windows Startup folder handled the execution.

WinRAR had over 500 million users when the bug was found. ✅ How to Stay Safe Update WinRAR: Ensure you are using version 5.70 or newer .

The flaw existed in unacev2.dll , a third-party library WinRAR used to unpack files. Path Traversal: Attackers could bypass folder restrictions.

This vulnerability allowed attackers to execute code remotely by simply having a user extract a specially crafted archive. 🛡️ The Vulnerability: CVE-2018-20250

The malware would run automatically the next time the user logged in. 📂 Technical Breakdown

RARLAB removed unacev2.dll entirely to fix the issue.