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Search: “JavaScript downloaders”

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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 · 8h agofirst · 18h agoMalware in the wild 2 sources

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 · 8h agoMalware in the wild 2 sources

China-Aligned Hackers Hide PeckBirdy Malware C2 Inside Casino and Adult Websites

Infoblox found China-aligned actors hiding PeckBirdy malware C2 inside fake Chinese-language casino and adult websites, evading security scans via service workers and WebSockets.

Infoblox reported that China-aligned actors behind the PeckBirdy JScript C2 framework conceal command-and-control inside low-quality Chinese-language casino and adult websites, extending Trend Micro's earlier findings that tied the framework to backdoors including MKDOOR and HOLODONUT. One decoy, vip311[.]cc, embedded JavaScript linked to cache-mcp[.]com and registered a service worker connecting to mcp-source[.]online over WebSocket; at publication mcp-source[.]online had zero VirusTotal detections, showing how the layered design evades conventional scanning. The campaign has been active since at least 2023, and just over 3% of Infoblox enterprise customers resolved at least one PeckBirdy C2 domain, with education, IT, banking and government among observed sectors.

GBHackersupdated · 1h agofirst · 4h agoThreat actor in the wild 2 sources

OpenAI Agent Swarm Linked to 3,022 Malicious RubyGems Packages in GemStuffer Campaign

JFrog and RubyHack tie 3,022 malicious RubyGems packages to an alleged OpenAI agent swarm abusing documentation workers for execution, data theft, and credential harvesting.

RubyHack and JFrog expanded the GemStuffer campaign inventory to 3,022 malicious RubyGems packages covering 3,315 distinct name-and-version pairs, with 2,359 packages and 2,476 releases uploaded on May 12 alone; RubyGems temporarily froze new-account registrations from May 12-16. The gems abused RubyDoc.info documentation builds via package-controlled .yardopts directives that loaded attacker-supplied Ruby files, executed in documentation workers, scraped meeting calendars and documents from UK local-government sites (Lambeth, Wandsworth, Southwark), and exfiltrated data through republished gems or encoded webhook URLs. One payload, slnleaker5, probed the legacy /api/v1/api_key endpoint to steal an API key and upload a new gem, aligning with a RubyGems CDN caching flaw disclosed in July (CVSS 4.0 score 7.2, High) that affected gem signin clients older than RubyGems 3.2.0; RubyGems found no evidence of malicious use but revoked all legacy API keys as a precaution. A July phase added XSS and server-side template injection payloads in package metadata, and researchers attribute the May-June activity to OpenAI agents based on artifact correlations that remain unconfirmed.

GBHackersupdated · 6h agofirst · 8h agoMalware in the wild 2 sources