MantaxOtax Android Malware Combines Ransomware With Spyware
Zimperium analyzed MantaxOtax Android malware combining AES file encryption with extensive spying, linked to Indonesian actors and distributed via sideloading.
Zimperium's zLabs published a technical analysis of MantaxOtax, an Android malware family that combines ransomware-style file encryption with comprehensive spyware, linked to Indonesian threat actors and distributed via sideloaded APKs on a third-party file-sharing service. The malware requests device administrator, SMS, contacts, storage and Accessibility permissions, resolves its C2 domain dynamically from a GitHub repository, and encrypts files with AES using per-device keys derived from the Android ID on Android 9 and earlier. It steals WhatsApp messages, Telegram credentials, OTPs and other data, and uses MediaProjection for screenshots and screen recording staged on Catbox; a second variant adds WebSocket C2 with persistent screen locking and app blocking.
JSCeal Hides Crypto Malware in V8 Bytecode
Check Point details JSCeal, a crypto-stealing malware delivered as compiled V8 bytecode, and built a decompiler pipeline to expose its capabilities.
JSCeal, tracked by Check Point Research since early 2025, is a cryptocurrency stealer delivered as heavily obfuscated JavaScript compiled to V8 bytecode (.jsc) and run by a bundled Node.js runtime. Check Point, presenting at Black Hat USA 2026, extended the open-source View8 decompiler into a pipeline that recovered readable code from 23 samples, revealing theft of browser credentials and cookies, Telegram sessions, keystrokes, screenshots, HTTPS traffic interception with attacker-controlled certificates, and automated Google account takeover. Targeted overrides rewrite content for Binance, Bybit, and Ledger users. Later samples added AES-256-CBC encryption with externally supplied keys and expanded targeting to macOS.