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.
Chrome 153 Fixes 230 Vulnerabilities, Including One 0-Day Exploited in the Wild
Google shipped Chrome 153 with 230 fixes, including CVE-2026-87491, a V8 out-of-bounds write zero-day exploited in the wild.
Chrome 153 (153.0.8010.36/.37) rolls out to Windows, Mac, and Linux with 230 security fixes, among the largest patch batches in recent Chrome history. The headline flaw is CVE-2026-87491, a Medium-severity out-of-bounds write in the V8 JavaScript and WebAssembly engine that Google confirmed is exploited in the wild; it was reported by Jihyeon Jeong of Compsec Lab at Seoul National University for a $2,500 bounty. The release also closes five Critical-rated flaws, including CVE-2026-87464, CVE-2026-87488, CVE-2026-87438, CVE-2026-87527, and CVE-2026-87628, mostly use-after-free and out-of-bounds write bugs in WebGL and Cast, plus 43 High-severity issues across ANGLE, PDFium, V8, DevTools, and Payments. Several bugs were surfaced with AI-assisted discovery tools, including OpenAI's Codex Security team, and top bounties reached $5,000 for CVE-2026-87504.