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3 stories in the last 7d

China-Linked Hackers Exploit Chrome-Windows Zero-Day Chain to Deploy GRIMWEDGE

Volexity attributes spear-phishing campaign exploiting Chrome-Windows zero-day chain to Chinese actors UTA0560 and APT31 deploying GRIMWEDGE and LONGTALE.

Volexity attributes a September 1, 2026 spear-phishing campaign targeting NGOs to China-linked UTA0560, which abused a reflected XSS flaw on a US university website to trigger a three-part exploit chain (CVE-2026-85046, CVE-2026-87491, CVE-2026-85880) escaping the Chrome V8 and browser sandboxes to deploy the GRIMWEDGE JavaScript backdoor with reconnaissance, file management, and command execution capabilities. The same chain was used near-simultaneously by JungleBamboo (APT31) to deploy SUPERSTOMP, installing the LONGTALE/GemStone credential-stealing Chrome extension masquerading as Google Gemini. The Chrome flaws were patched in Chromium but not yet in stable Chrome, creating an unusual patch-gap zero-day window attackers raced to exploit.

The Hacker Newsupdated · 1d agofirst · 1d agoThreat actor in the wild 23 sourcesCVE-2026-85046CVE-2026-87491CVE-2026-858801· 1 read

China-Linked Hackers Exploit Sogou One-Click RCE to Deploy GRAYRABBIT Backdoor

China-linked UNC3569 exploited CVE-2026-51990 in Sogou Input Method to deploy the GRAYRABBIT backdoor in active espionage intrusions.

Gen Threat Labs discovered UNC3569 exploiting CVE-2026-51990, a one-click RCE in Tencent's Sogou Input Method for Windows that chains an insecure sgbiz: protocol handler with an unsandboxed Chromium 80 CEF webview. The chain weaponizes CVE-2021-38003 (V8 type confusion) to run shellcode that DLL-sideloads via 7z.exe/7z.dll and deploys the GRAYRABBIT backdoor, which beacons over RC4-encrypted raw TCP 443 to mail.uaiubifas[.]top. Tencent patched the issue in version 16.3.0.3498, released via automatic updates on April 21, 2026. UNC3569 is a PRC-nexus espionage actor targeting government, education, technology, and financial sectors across East and Southeast Asia.

GBHackersupdated · 2d agofirst · 2d agoThreat actor in the wild 3 sourcesCVE-2026-51990CVE-2021-380031

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 · 4h agofirst · 6h agoThreat actor in the wild 2 sources