One Click on a Malicious Link Lets Hackers Backdoor Sogou Input Method Users
Actively exploited one-click flaw in Sogou Input Method (CVE-2026-51990) let UNC3569 deploy the GRAYRABBIT espionage backdoor on Windows.
Gen Digital researchers found three weaknesses in Sogou Input Method's sgbiz protocol handler that chain into a one-click RCE running with the signed-in user's permissions. UNC3569 used the chain in an active intrusion, leveraging an unsandboxed Chromium 80 embedded browser, the known V8 flaw CVE-2021-38003, and DLL sideloading via 7-Zip to deploy the GRAYRABBIT backdoor. Tencent fixed the issue in version 16.3.0.3498 within 12 days of disclosure; Sogou is used by hundreds of millions of people, mainly in China.
BlueMoon exploit kit turns Chrome and Windows flaws into attacks
Proofpoint documents BlueMoon exploit kit used by four espionage groups to chain Chrome V8 and Windows flaws via phishing, all now in CISA's KEV.
Proofpoint identified a shared Chrome and Windows exploit kit, BlueMoon, used by four espionage groups against Chrome on Windows within days of one another. Attacks began with phishing emails leading to web pages that exploited two Chrome V8 vulnerabilities, followed by a Windows flaw to escape browser protections and gain higher privileges. The Chrome flaws were patched in Stable on September 3 and 8, 2026, the Windows flaw was fixed in September Patch Tuesday, and all three were actively exploited and added to CISA's KEV catalog. Researchers found clues, but no conclusive evidence, that the kit was developed with AI assistance.
Hackers Can Rent VectraRAT for $250 a Month to Take Control of Windows PCs
SOCRadar uncovered VectraRAT, a previously undocumented $250-per-month Windows RAT rental service delivered via Amadey and ClickFix lures.
SOCRadar's Threat Research Unit identified VectraRAT, a rental-only remote access trojan sold by a developer known as Vectra (formerly Nyxel), after an exposed online directory revealed samples, licenses, and operator logs across ten-plus servers. The toolkit includes a Linux control server, Windows implant, payload builder, and VectraHub panel, enabling hidden desktop access, keylogging, command execution, credential theft, file transfer, proxying, and silent privilege escalation. Of victims with OS data, 48 percent ran corporate Windows editions, and researchers recorded 38 genuine victim sessions in under a week, including file theft from business systems. Distribution occurs through the Amadey loader and ClickFix pages impersonating TurboTax, with custom TCP-based C2 over non-standard ports.
UBoatRAT Navigates East Asia
Unit 42 discovers UBoatRAT, a new custom RAT targeting South Korean and video-game industry personnel, delivered via Google Drive with GitHub-based C2 and BITS persistence.
Unit 42 identified UBoatRAT, a new custom remote access trojan first found in May 2017, whose initial version used a public Hong Kong blog service and a compromised Japanese web server for command and control. The latest variants target personnel or organizations related to South Korea or the video games industry, are delivered through Google Drive, and masquerade as Microsoft Word, Excel, or folder icons. The RAT checks for virtualization software and domain join, retrieves its C2 address from a Base64-encoded string in a GitHub-hosted file, uses a custom XOR-encrypted C2 protocol, and maintains persistence via Windows Background Intelligent Transfer Service (BITS) jobs that survive reboots.