Exploring Compiled V8 Javascript Usage In Malware


In recent months, CPR has been investigating the usage of compiled V8 JavaScript by malware authors. Compiled V8 JavaScript is a lesser-known feature in V8, Google’s JavaScript engine, that enables the compilation of JavaScript into low-level bytecode.

This technique assists attackers in evading static detections and hiding their original source code, rendering it almost impossible to analyze statically. To statically analyze compiled JavaScript files, Check Point researchers employed a newly-developed custom tool named ”View8”, specifically designed for decompiling V8 bytecode to a high-level readable language. Using View8, they decompiled thousands of malicious compiled V8 applications, spanning various malware types, such as Remote Access Tools (RATs), stealers, miners and even ransomware.

Read more…
Source: Check Point


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