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KREMLIN Banking Malware Infects Over 1,500 Systems With Malicious Chrome Extension

Elastic tracks KREMLIN banking malware that used fake Brazilian bank JavaScript lures to deploy malicious Chrome and Edge extensions on 1,515 systems.

Elastic researchers tracked the KREMLIN banking malware operation across seven campaigns over 15 months, infecting 1,515 systems, 98.75% of them in Brazil. Portuguese-language lures posing as bank records and invoices deploy a hostile 'AVSync' extension into Chrome and Edge profiles that harvests passwords, session cookies, keystrokes and screenshots. Loaders check for sandboxes, create scheduled tasks and fetch fresh infrastructure from an Ethereum smart contract; a network canary takeover temporarily disrupted infections.

Cyber Security Newsupdated · 15h agofirst · 1d agoMalware in the wild 3 sources

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 · 3d agoMalware in the wild

Malicious Twitch Extension Exposes OAuth Tokens of 30,000 Chrome and Firefox Users

Malicious 'Twitch Enhanced Viewer | JeetBot' browser extension stole live OAuth session tokens from roughly 31,000 Chrome and Firefox users.

Socket.dev found the cross-store extension 'Twitch Enhanced Viewer | JeetBot' rerouted Twitch playlist requests through operator-controlled proxies, attaching the victim's account-level OAuth token as a URL parameter where it could be logged in cleartext. About 30,000 Chrome and 552 Firefox installs were exposed, with tokens forwarded for nearly every watched channel to infrastructure tied to a Russian commercial bot service. The stolen bearer token enables chat, whisper, account-setting access and channel-point spending without the password or 2FA.

Cyber Security Newsupdated · 2d agofirst · 2d agoMalware in the wild 2 sources

19 Chrome and Edge Extensions Found With Wallet-Stealing and Crypto

Socket found 19 malicious Chrome and Edge extensions, active since February 2024, stealing wallet seed phrases and credentials and draining crypto from about 80,000 users.

Socket researcher Karlo Zanki documented a cluster of 18 Chrome and one Edge extensions with wallet secret stealing and cryptocurrency draining capabilities, tracked as campaign Superior and possibly active since February 2024. The actor created 14 extensions and bought five legitimate ones, later pushing malicious updates; the largest, Enable Right Click & Copy, has roughly 80,000 installs across both browsers. The extensions maintain WebSocket C2 connections with endpoint rotation, strip CSP headers, and load 16 modules including multi-chain wallet drainers, hardware-wallet seed-phrase harvesters, credential grabbers, and ClickFix-style lures.

The Hacker News · 19d agoMalware in the wild

KREMLIN Banking Malware Hijacks Chrome and Edge to Steal Credentials and Session Tokens

Elastic Security Labs details KREMLIN, Brazilian banking malware using malicious Chrome/Edge extensions and Ethereum smart contracts to steal credentials and session tokens.

Elastic Security Labs documents KREMLIN (tracked as REF9334), a Brazilian banking malware toolkit active since at least May 2025 that impersonates a dozen Brazilian banks. It uses multi-stage JavaScript loaders, a C++ installer that DLL-sideloads via a legitimate SentinelOne binary, and a malicious Chrome/Edge extension named 'AVSync System Inc.' Ethereum smart contracts act as dead-drop resolvers for C2 endpoints, a shift that occurred May 19, 2026, making infrastructure hard to disrupt. The extension harvests cookies, sessionStorage/localStorage, browsing history, screenshots, and full page HTML via WebSocket plus CSS-disguised polling endpoints. The group has run seven distinct campaigns and also distributes Pulsar RAT and Remcos RAT.

The Hacker Newsupdated · 1d agofirst · 1d agoMalware in the wild 2 sources

40 Malicious Firefox Extensions Pose as Web3 Products to Steal Wallet Secrets

Socket found 40 malicious Firefox extensions impersonating OKX, Rabby Wallet, and TronLink to steal cryptocurrency wallet recovery phrases and private keys.

The Socket Threat Research team identified 40 malicious Firefox extensions masquerading as Web3 products including OKX, Rabby Wallet, and TronLink, part of a broader set of 77 add-ons sharing source code and infrastructure overlaps. The campaign, dubbed Offside Wallet Theft Factory, has been active since March 2026 and remains unattributed. Of the 40 confirmed malicious extensions, 15 capture recovery phrases and private keys exfiltrated through Cloudflare Workers, 13 modified Rabby Wallet builds exfiltrate serialized keyrings before local encryption, seven use attacker-controlled Supabase projects as remote switches, and five capture credentials and clipboard data via hard-coded C2. Some extensions began as sports score or utility shells before being repurposed into wallet stealers under the same Firefox ID.

The Hacker News · 28d agoMalware in the wild

Malicious Twitch Extension Exposes 31,000 Users' OAuth Tokens

Malicious Twitch extension 'Twitch Enhanced Viewer | JeetBot' forwarded live OAuth session tokens of roughly 31,000 users to Russian JeetBot proxy servers.

Socket research found the cross-store extension Twitch Enhanced Viewer | JeetBot (about 30,000 Chrome users and 552 Firefox users) routing Twitch video requests through JeetBot proxy servers with the account-scoped OAuth bearer token appended in cleartext as a URL query parameter. Version 4.x builds, including 4.8 from January 2026, posted captured tokens to dedicated set-token endpoints on JeetBot infrastructure with backups on two Deno services. Token holders can read and send whispers, post in chat, and spend channel points without a password or 2FA; listings were still live at publication and users are advised to remove the extension and re-authenticate.

Infosecurity Magazine · 2d agoMalware in the wild 2 sources

Twitch extension with 30K installs exposes users’ OAuth tokens

Twitch extension with 30,000+ installs exfiltrates users' OAuth session tokens to Russian-run JeetBot proxy servers.

Socket analysis shows the "Twitch Enhanced Viewer | JeetBot" browser extension, with over 30,000 installs on the official Chrome and Firefox stores, captures the Twitch web client's authorization header and extracts the user's OAuth token. The token is appended as an auth= URL parameter to video playlist requests routed through JeetBot proxy servers, landing in cleartext request logs retrievable by the Russian-language bot service vendor; ten hardcoded Russian-language channels are exempted. Earlier versions used more explicit token exfiltration, and the extension remained live in both stores at publication. Socket recommends removing the extension, disconnecting all Twitch sessions, and re-authenticating.

BleepingComputer · 2d agoMalware in the wild

PEEP Turns Chrome and Edge Into Post-Compromise Backdoors for Host Command Execution

SOCRadar disclosed PEEP, a post-exploitation Chromium extension toolkit that turns Chrome and Edge into host-level backdoors via native messaging and C2 polling.

SOCRadar researchers detailed PEEP, a Chromium-based post-exploitation toolkit masquerading as a 'Smart Bookmarks' extension injected directly into Chrome and Edge profiles by forging Secure Preferences integrity values, bypassing Web Store checks. A native-messaging host binary (nm_host.exe) extends the browser agent to host-level command execution, file management, credential theft, and session hijacking, while the extension polls C2 endpoints at 206.237.30.232 or xfjcc.fun every 30 seconds over plaintext HTTP and exfiltrates browsing history, cookies, and tab metadata. PEEP is derived from the open-source RedExt red teaming framework, adds PowerShell persistence scripts, and includes a Linux-targeting Python script, suggesting cross-platform intent. The activity is unattributed but contains Chinese-language artifacts; a C2 /health endpoint showed 34 agent entries and 10 active sessions.

The Hacker News · 9d agoMalware in the wild1

Malware bypasses browser checks to force install Chrome, Edge extensions

Elastic Security Labs detailed KREMLIN, a Brazilian banking malware that silently installs malicious Chrome and Edge extensions, with 1,515 confirmed infections.

Elastic Security Labs analyzed KREMLIN, a toolkit used by a Brazilian operation in at least seven campaigns since May 2025 that impersonates 12 banks to trick users into opening a JavaScript file disguised as a bank receipt or invoice. After anti-sandbox checks, it downloads Node.js, persists via a scheduled task, and fetches payload locations from an Ethereum smart contract, hiding payloads in JPEG images on Internet Archive. The toolkit bypasses Chromium integrity mechanisms to install unapproved Chrome/Edge extensions masquerading as AVSync that steal cookies, keylog form input, capture screenshots, and intercept HTTP traffic, while recent campaigns deployed the REMCOS RAT and earlier ones Pulsar RAT. Elastic confirmed 1,515 infected systems, almost all in Brazil, and disrupted the campaign by registering an anti-sandbox canary domain; the linked wallet handled roughly 20,800 USDT incoming and 19,000 USDT outgoing.

BleepingComputer · 15h agoMalware in the wild 3 sources

Malicious Twitch Browser Extension Leaks OAuth Tokens From Nearly 31,000 Users

Malicious Twitch extension 'Twitch Enhanced Viewer | JeetBot' leaked OAuth tokens from nearly 31,000 users to Russian bot-service proxy servers.

Socket researchers found the 'Twitch Enhanced Viewer | JeetBot' browser extension forwarded users' live Twitch OAuth tokens as an &auth= query parameter to operator-controlled proxy servers, affecting about 30,000 Chrome users and 604 Firefox users. The tokens, written in cleartext to proxy logs, are bearer credentials granting access to chat, whispers, and account settings without password or 2FA. The operator is a Russian commercial Twitch/Kick/VK-Live bot SaaS linked to Cyprus-based developer Aleksandr Popov; earlier v4.x builds also POSTed tokens to a set-token endpoint. Firefox add-on version 85.8.7 stops the token forwarding, but previously transmitted tokens remain valid until revoked.

The Hacker News · 3d agoMalware in the wild

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.

GBHackers · 1d agoMalware in the wild 2 sources

ThreatsDay: 200 Android Flaws, Browser-Built Phishing, 119K Scam Shops + 23 More Stories

Hacker News ThreatsDay digest: malicious browser extensions, AI-agent intrusions, NCSC shadow AI warning, M&A wire fraud, and 119,000-domain fake shops.

Socket found four malicious Chrome and Firefox extensions (J7Tracker, VREO, Orbit Tracker) stealing session tokens and wallet data from Axiom Trade and Padre users via attacker-controlled Vercel deployments. Hunt.io reported a Chinese-speaking operator using Claude Code, Alibaba Qwen, and DeepSeek with the SecFlow orchestration framework to automate intrusions against government and financial targets in Afghanistan, Thailand, Taiwan, and the US. The UK NCSC warned shadow AI use risks breaches and regulatory failure, Microsoft announced privacy-preserving Windows Age APIs, and Gen Digital described fake M&A wire-fraud scams. A 119,000-domain fake-shop operation called DoppelCart was also highlighted.

The Hacker News · 6d agoIndustry in the wild

One Exploit Chain, Two Espionage Campaigns: Chrome and Windows Under Fire

Two China-linked APT groups reused identical Chrome/Windows zero-day chain against NGOs, deploying GRIMWIDGE backdoor and LONGTALE credential-stealing extension.

Volexity reports that China-linked actors UTA0560 and JungleBamboo (APT31/TA412) ran byte-identical Chrome/Windows exploit chains against NGOs starting September 1, 2026, combining Chrome type confusion CVE-2026-85046, WebAssembly sandbox escape CVE-2026-87491, and Windows kernel flaw CVE-2026-85880. The Chrome bug was fixed in Chromium source but not yet shipped to Chrome users, making it an effective zero-day with an unusual patch gap. UTA0560 delivered the in-memory GRIMWEDGE JScript backdoor, while JungleBamboo deployed the SUPERSTOMP loader installing LONGTALE, a malicious Chrome extension disguised as Google Gemini that steals cookies, session tokens, and keystrokes. Volexity assesses with low confidence the exploit chain was sold or shared among different Chinese end-users.

Microsoft security advisory – September 2026 monthly rollup (AV26-896) – Update 1

Canada's Cyber Centre relays Microsoft's September 2026 rollup; CISA added exploited zero-days CVE-2026-85880 and CVE-2026-81963 to KEV.

Advisory AV26-896 from the Canadian Centre for Cyber Security summarizes Microsoft's September 2026 monthly security rollup, listing affected products across Windows, Office, .NET, Azure, Exchange and SQL Server. It notes Microsoft confirmed CVE-2026-81963 and CVE-2026-85880 have been exploited. On September 8, 2026, CISA added both CVEs to its Known Exploited Vulnerabilities catalog, and administrators are urged to apply the updates.

Fake AI trading agent steals crypto wallet passwords

Fake AI crypto trading agent sites deliver Needle Stealer, which replaces browser wallet extensions to steal wallet passwords, HP reports.

HP researchers tracked campaigns between April and June 2026 in which a fake AI trading agent site, tradingclaw[.]pro, distributed a Microsoft-signed OLEView executable that DLL side-loads a malicious iviewers.dll and launches Needle Stealer via process hollowing. Needle replaces one of seven browser wallet extensions, including MetaMask, Coinbase Wallet, and Phantom, to capture wallet passwords. Related campaigns used QR-code invoice phishing leading to fake OneDrive pages, Phantom Stealer sold as a penetration testing tool with VBScript-to-PowerShell steganographic loaders, and image-hidden payloads delivering XWorm, PureLogs Stealer, and Formbook; a perceptual-hash VirusTotal search found about 400 distinct rigged images.

Help Net Security · 2h agoMalware in the wild

The September 2026 Security Update Review

ZDI's September 2026 Microsoft update review lists two already-exploited Windows EoP zero-days and dozens of critical RCEs across Office, SQL Server, and Windows services.

The review catalogs Microsoft's September 2026 fixes, marking CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack) as already exploited elevation-of-privilege issues. It also lists critical RCE flaws in Office, Word, Excel, PowerPoint, Outlook, SQL Server, Windows DNS, DHCP and Failover Cluster, plus graphics component RCEs. Azure-side fixes include Entra ID, Copilot Studio, Azure AI Language and Azure AD B2C elevation-of-privilege flaws.