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


Sign up for our Newsletter


Related:

  • Triada strikes back

    April 25, 2025

    Older versions of Android contained various vulnerabilities that allowed gaining root access to the device. Many malicious programs exploited these to elevate their system privileges and gain persistence. The notorious Triada Trojan also used this attack vector. With time, the vulnerabilities were patched, and restrictions were added to the firmware. Specifically, system partitions in recent ...

  • Lumma Stealer – Tracking distribution channels

    April 21, 2025

    The evolution of Malware-as-a-Service (MaaS) has significantly lowered the barriers to entry for cybercriminals, with information stealers becoming one of the most commercially successful categories in this underground economy. Among these threats, Lumma Stealer has emerged as a particularly sophisticated player since its introduction in 2022 by the threat actor known as Lumma. Initially marketed as ...

  • New Rust Botnet “RustoBot” is Routed via Routers

    April 21, 2025

    FortiGuard Labs recently discovered a new botnet propagating through TOTOLINK devices. Unlike previous malware targeting these devices, this variant is written in Rust—a programming language introduced by Mozilla in 2010. Due to its Rust-based implementation, we’ve named the malware “RustoBot.” In January and February of 2025, FortiGuard Labs observed a significant increase in alerts related to ...

  • Phishing attacks leveraging HTML code inside SVG files

    April 21, 2025

    With each passing year, phishing attacks feature more and more elaborate techniques designed to trick users and evade security measures. Attackers employ deceptive URL redirection tactics, such as appending malicious website addresses to seemingly safe links, embed links in PDFs, and send HTML attachments that either host the entire phishing site or use JavaScript to ...

  • Cascading Shadows: An Attack Chain Approach to Avoid Detection and Complicate Analysis

    April 16, 2025

    In December 2024, Palo Alto Unit 42 researchers uncovered an attack chain that employs distinct, multi-layered stages to deliver malware like Agent Tesla variants, Remcos RAT or XLoader. Attackers increasingly rely on such complex delivery mechanisms to evade detection, bypass traditional sandboxes, and ensure successful payload delivery and execution. The phishing campaign we analyzed used deceptive ...

  • BPFDoor’s Hidden Controller Used Against Asia, Middle East Targets

    April 14, 2025

    The stealthy rootkit-like malware known as BPFDoor (detected as Backdoor.Linux.BPFDOOR) is a backdoor with strong stealth capabilities, most of them related to its use of Berkeley Packet Filtering (BPF). In a previous article, Trend Micro researchers covered how BPFDoor and BPF-enabled malware work. BPFDoor has been active for at least four years, with a report by ...