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.
KREMLIN Banking Malware Bypasses Chrome Security to Steal Banking Sessions
Elastic Security Labs details KREMLIN, a Brazilian banking malware that implants malicious Chrome and Edge extensions by forging Chromium integrity values to steal banking sessions.
Elastic Security Labs tracks the KREMLIN banking malware operation as REF9334, active since at least May 2025 across seven campaigns primarily targeting 12 Brazilian banks. The malware is installed by a victim-run JavaScript loader, achieves scheduled-task persistence, and side-loads a malicious DLL via SentinelOne's SentinelMemoryScanner.exe. It modifies Chrome and Edge Secure Preferences files, enables developer mode, and regenerates Chromium MAC values to silently install extensions, while extracting browser encryption material including the newer App-Bound OSCrypt key. An Ethereum smart contract serves as a dead-drop resolver for C2 config; Elastic disrupted over 1,500 infections via a canary domain.
HBO Max Reddit Account Hijacked to Spread PasteSwitch ClickFix Malware
Hijacked HBO Max verified Reddit account ran 108 ClickFix malvertising ads delivering AMOS and Amatera stealers plus crypto clippers to macOS and Windows users.
Threat actors hijacked HBO Max's verified Reddit account (u/hbomax) to run 108 malicious ClickFix ads over 48 hours in a campaign tracked as PasteSwitch, researched by Hudson Rock and ADAMnetworks. macOS victims were served curl | zsh chains deploying MacSync and Atomic macOS Stealer (AMOS), which harvest browser credentials, Telegram data, Apple Notes, and macOS passwords, while fake Ledger, Trezor, and Exodus apps targeted BIP39 seed phrases. Windows users received an InstallFix chain using an MP3/HTA polyglot with mshta and PowerShell, scheduled-task persistence, AMSI disabling, and in-memory Amatera Stealer that hid C2 traffic (77.91.65.13:443) behind a facebook.com TLS SNI. AnimateClipper and ZigClipper components swapped copied crypto wallet addresses and used Binance Smart Chain contracts as mutable C2 dead drops; Reddit paused the ads and the initial access path remains undisclosed.