30
30
WeChat Zero-Click Worm Took Over Accounts on iPhone and Android via Incoming Calls
Researchers demonstrated a zero-click WeChat worm that hijacked accounts via incoming calls; Tencent blocked the exploit server-side after July disclosure, no real attacks reported.
Security firm Calif built a worm that seized WeChat accounts via incoming calls without any target interaction, demonstrating it spreading across three test phones (Android to iPhone to Android). Once exploited, the attacker gains full control of the WeChat account, including messages, calls, payments, and mini programs, though not the phone itself. Tencent mitigated the flaw server-side, confirmed blocked on 28 August, shipping WeChat 8.0.77 for Android and 8.0.76 for iOS on 21 August. No CVE has been assigned, Tencent published no advisory, and no attacks in the wild have been reported; WeChat/Weixin counts 1.439 billion monthly active users.
68
30
30
47
30
CDN Tsunami Attack Abuses HTTP/3 Translation for Up to 350x DoS Amplification
Researchers disclosed two DoS attacks exploiting CDNs' HTTP/3-to-HTTP/1.1 translation to amplify low-bandwidth requests up to 350x against origin servers.
Researchers named the two techniques HTTP/3 Bandwidth Amplification (HBA) and HTTP/3 Connection Amplification (HCA), exploiting the gap where CDNs speak HTTP/3 to browsers but only HTTP/1.1 to origins. All six tested CDNs (Alibaba, Baidu, Cloudflare, CloudFront, Fastly, Tencent) were susceptible to HBA, and five to HCA, with Cloudflare immune to HCA because it buffers full requests before opening backend connections. Attackers using under 5 Mbps forced over 100 Mbps at origins, and the 350x factor applies only to Alibaba, Baidu, and Tencent, which support the QPACK dynamic table. Testing identified 42,330 potentially vulnerable subdomains out of 151,685 hosted on the six providers across the Tranco Top 1M.
65
42
30
WeChat Worm Can Hijack Accounts Without Victims Answering Calls
Researchers demoed WeWorm, a zero-click WeChat worm hijacking accounts via incoming VoIP calls using a memory corruption flaw; Tencent patched it in August.
Researchers at Calif exploited a memory corruption bug in WeChat's VoIP system, taking over accounts through an incoming call even if the victim never answers or touches the phone. The attacker must already be a WeChat contact, but compromising a friend's account bypasses this, and chained calls spread the worm across three Android and iOS test phones in seconds. Tencent fixed the flaw in Android 8.0.77 and iOS 8.0.76 released in August, and researchers found no evidence of real-world exploitation. WeChat and Weixin reported 1.418 billion combined monthly active users at the end of 2025.
66
42
45
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.
80
WeChat worm could pwn a friend before they even answered the call
Calif researchers demoed WeWorm, a zero-click WeChat VoIP memory-corruption worm enabling account takeover; Tencent patched it August 21.
Security firm Calif found a memory corruption bug in WeChat's VoIP stack that let a trusted contact take over a user's account simply by calling them, without the call being answered. The demo worm then called the victim's contacts to self-propagate across iOS and Android; declining the call prevented infection. Tencent pushed fixes on August 21, and Calif said chaining the bug with other Android and iOS flaws could yield full device control. Calif used AI to find the vulnerability and build its first RCE exploit in about two days.
68
30
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.
82
60
42
30
55
60
55
60
“Zero-click” WeChat worm could hijack accounts and spread via a single call
Researchers discovered a critical memory corruption flaw in WeChat's VoIP stack enabling a zero-click worm, WeWorm, that hijacks accounts via calls; Tencent patched it.
Calif researchers weaponized a memory corruption issue in WeChat's VoIP stack into "WeWorm", a worm that spreads through WeChat calls without user interaction, hijacks each victim's account, and propagates via saved contacts across iOS and Android, potentially reaching millions of devices within hours. Exploitation takes seconds and grants full account control, and chaining with other reported Android/iOS bugs could lead to full device control. Tencent issued updated WeChat versions for iOS and Android and applied server-side mitigations; technical details remain withheld. WeChat has over a billion users, overwhelmingly in China.
82
42
60
60
60
AI-Infra-Guard: Open-source security scanner for AI systems
Tencent's Zhuque Lab open-sourced AI-Infra-Guard, a scanner that fingerprints AI services, checks 1,600+ CVEs, and evaluates MCP skills.
AI-Infra-Guard fingerprints running AI services such as Ollama, vLLM and ComfyUI, checks them against more than 1,600 known CVEs, and inspects MCP servers and agent skills across 14 risk categories. Its SkillTrustBench judging set contains 5,520 human-labeled samples, with false positive rates of 1.20%–18.67% depending on the judging model. Users include ICBC, China Merchants Bank, China Telecom, Lenovo, vivo and Bilibili. Release 4.1.9 hardened scanning agents against indirect prompt injection, and the open-source build ships without authentication, requiring a reverse proxy with Basic Auth or an IP allowlist.
35
WeWorm – First 0-Click Worm Spreading Through WeChat Calls Across iOS and Android
Researchers demonstrated WeWorm, a zero-click worm exploiting a memory-corruption flaw in WeChat's VoIP stack to spread via calls across iOS and Android.
Security firm Calif published WeWorm, a proof-of-concept zero-click worm exploiting a memory-corruption bug in WeChat's VoIP stack to spread through voice calls on iOS and Android without the victim answering. The demo chained a Pixel 10a, an iPhone 17e, and a second Pixel 10a, compromising each device while the call was still ringing and giving full control of the WeChat account. The attacker must already be on the victim's friend list, but compromised contacts become the propagation layer across a platform with over 1.4 billion monthly users. Calif reported the bug to Tencent in July 2026, and Tencent has since mitigated it; full technical details are withheld for a later conference presentation.
68
42
42
30
42
42
60
35
60
60