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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.

Security Affairs · 9d agoMalware1

Breaking the Seal: Static Deobfuscation of JSCeal’s Compiled V8 Bytecode

Check Point's hasherezade details static deobfuscation of JSCeal, a V8-bytecode stealer targeting cryptocurrency applications since March 2024.

JSCeal is an infostealer distributed as compiled V8 bytecode (.jsc) executed by a bundled Node.js runtime, aimed at cryptocurrency applications. Other vendors track the same family under the names WEEVILPROXY or MeadowLocust. Check Point Research has tracked the campaign since early 2024, with activity dating back to March 2024. The write-up presents a static approach to unpacking the bytecode without executing it.

Check Point Research · 16d agoMalware in the wild1

JSCeal Malware Can Bypass Google Authentication Using Stolen Session Cookies

Check Point details JSCeal, a V8-compiled JavaScript stealer that replays stolen cookies to bypass Google authentication, spread via crypto malvertising.

Check Point Research's new report analyzes JSCeal, a compiled V8 JavaScript malware obfuscated with javascript-obfuscator using RC4-protected strings, control-flow flattening, and proxy functions. Delivered through fake TradingView installers on malvertising sites overlapping the WEEVILPROXY/MeadowLocust and SourTrade campaigns, it harvests cookies, passwords and OAuth tokens from Chromium browsers, records keystrokes and screenshots, and can replay stolen Google session cookies to bypass authentication. It also installs a local proxy with service-specific handlers for Binance, Bybit, and Ledger to intercept and modify cryptocurrency-related traffic.

The Hacker News · 9d agoMalware in the wild1

The extension you never installed: KREMLIN forges Chrome's own integrity checks to steal banking sessions

Elastic details KREMLIN, a Brazilian banking malware whose malicious Chrome/Edge extension forges Chromium integrity checks to steal sessions.

Elastic Security Labs tracked operation REF9334 and its KREMLIN toolkit, a Brazilian banking malware campaign impersonating twelve banks across seven campaigns since May 2025. The infection chain uses multi-stage obfuscated JavaScript loaders with sandbox checks (file and process counting), scheduled-task persistence, and an Ethereum smart contract acting as a dead-drop resolver for C2 and payload URLs, abusing Archive.org for hosting. The malicious browser extension bypasses Chromium integrity mechanisms by manipulating Secure Preferences and regenerating required HMACs and App-Bound encrypted hashes. Threat Command disrupted over 1,500 infections by registering the kill-switch canary domain.

Elastic Security Labs · 2d agoMalware in the wild

Exploring the Latest Mispadu Stealer Variant

Unit 42 found a new Mispadu infostealer variant targeting Mexican users via malicious .url files exploiting the SmartScreen CVE-2023-36025 bypass.

Unit 42 discovered a new variant of Mispadu Stealer, a Delphi-based banking trojan first reported in 2019, found while hunting for the Windows SmartScreen bypass CVE-2023-36025. The campaign uses crafted .url files referencing UNC network-share paths with an HTTP port (@80) that forces payload retrieval over WebDAV via rundll32.exe, avoiding SmartScreen warnings. Analyzed samples (~4 KB, compiled 2023-11-12) predate the CVE publication, and ZIP payloads were likely distributed as email attachments, primarily targeting users in Mexico.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wildCVE-2023-360251