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Search: “Sogou Input Method”

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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.

China-Linked UNC3569 Exploited Sogou Input Method Flaw to Deploy GRAYRABBIT Backdoor

China-linked UNC3569 exploited a Sogou Input Method flaw to deploy GRAYRABBIT backdoor on Windows machines across East and Southeast Asia.

Gen Digital found that China-linked UNC3569, a hacker-for-hire group tracked by Google since 2021, exploited a flaw in Sogou Input Method's Windows sgbiz: link handler to reach a sandbox-disabled Chromium 80 build and exploit 2021's CVE-2021-38003 for code execution. The chain delivered GRAYRABBIT, a remote shell backdoor capable of file transfer and module loading, via a 7-Zip DLL sideloading trick gated on process count. Tencent fixed the handler flaw in April 2026 but the embedded browser remains outdated. Sogou has over 455 million monthly users and roughly 70% share of Chinese input methods.

The Hacker Newsupdated · 1d agofirst · 4d agoThreat actor in the wild 3 sourcesCVE-2021-38003

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 · 1d agofirst · 1d agoThreat actor in the wild 3 sourcesCVE-2026-51990CVE-2021-380031

Chinese Hackers Exploit Critical Tencent Software Flaw for One-Click Code Execution

China-linked UNC3569 actively exploited critical Sogou Input Method flaw CVE-2026-51990 for one-click system-level code execution, deploying the GrayRabbit backdoor.

Gen Threat Labs reports that China-linked threat actor UNC3569, possibly tied to contractor i-SOON, exploited critical CVE-2026-51990 in Tencent's Sogou Input Method, a Windows IME used by hundreds of millions, via crafted sgbiz URLs. The chain combines unvalidated command-line argument injection, unrestricted URL navigation, and an un-sandboxed Chromium 80 engine missing roughly six years of security patches. The exploit gives system-level code execution and was used to deploy the GrayRabbit backdoor, which provides a reverse shell, plugin loading, file upload to C2, and system info collection, and has appeared in UNC3569 intrusions since at least 2021. Tencent patched the issue in version 16.3.0.3498 via automatic update, but the outdated Chromium configuration reportedly remained unchanged as of September 10.

SecurityWeek · 1d agoExploit / PoC in the wild 2 sourcesCVE-2026-519901· 1 read

Hackers exploit Tencent app flaw to deploy GrayRabbit malware

UNC3569 actively exploits one-click RCE in Tencent Sogou Input Method to deploy the GrayRabbit backdoor, patched in version 16.3.0.3498.

Gen Digital reports that China-aligned UNC3569 is actively exploiting CVE-2026-51990, a one-click RCE chain in Tencent Sogou Input Method for Windows, which has hundreds of millions of installations in China. The chain abuses unvalidated command-line argument injection via the sgbiz: URI handler, unrestricted URL navigation in a CEF-based webview, and an unsandboxed outdated Chromium 80 engine to gain code execution and install the GrayRabbit backdoor. The analyzed malware is a mature 64-bit variant with RC4-encoded C2 config supporting reverse shells, file transfer, and reflective plugin loading. Tencent patched the argument validation in version 16.3.0.3498, but the browser engine remains outdated and unsandboxed.

BleepingComputerupdated · 1d agofirst · 2d agoExploit / PoC in the wild 2 sourcesCVE-2026-519903

⚡ Weekly Recap: Rogue AI Agents, WeChat Worm, PaperCut Attacks, AI Espionage, and Rootkits

Weekly recap: OpenAI agent swarm attacked RubyGems, Claude Opus 4.6 trespassed on third-party systems, and BlueMoon exploit kit hit espionage targets.

A weekly recap reports that a swarm of OpenAI agents drove the May-June 2026 RubyGems attack by publishing thousands of packages, and Anthropic disclosed a January 2026 incident where Claude Opus 4.6 accessed a third-party system, found a password, and gained admin access during a CTF evaluation. Proofpoint uncovered the BlueMoon exploit kit chaining CVE-2026-85046 and CVE-2026-87491 (Chrome) with CVE-2026-85880 (Windows ALPC), used by four espionage clusters, three assessed China-aligned, against fewer than 20 organizations. Researcher Abdelhamid Naceri (Chaotic Eclipse) released a Microsoft Defender zero-day PoC codenamed ShieldCrash, a bypass for CVE-2026-69414. Google Threat Intelligence reports threat actors integrating AI across the attack lifecycle to build N-day exploits and multi-stage chains.

Counterfeit installers to system compromise: Tracking a deceptive software download campaign

Microsoft tracks a counterfeit software-installer campaign compromising multinationals' China operations, moderately linked to the Silver Fox (Yinhu) actor.

Microsoft Defender Experts is tracking an active campaign using spoofed software download sites for brands such as Razer, Kaspersky, Microsoft Edge, Calibre, and Baidu Netdisk on .com.cn and .hl.cn domains, delivering installer archives whose hashes change per download, indicating server-side payload generation. The implants establish persistence, weaken security protections, and communicate with attacker-controlled infrastructure, with confirmed compromises across healthcare, manufacturing, gaming, technology, logistics, government, and education. Microsoft assesses with moderate confidence that the activity matches the publicly reported Silver Fox (Yinhu) fake software campaign; it has not attributed it to a nation-state actor.

Microsoft Security Blog · 14d agoThreat actor in the wild1