Calif

Researchers Create 0-Click WeChat Worm That Hijacks Accounts via Incoming Calls

Security researchers at Calif have developed a 0-click worm capable of compromising WeChat accounts through incoming voice calls without any user interaction. The exploit requires only that the attacker already exists in the victim's contact list and works across Android and iOS devices. In demonstrations, an infected Android device called an iPhone to seize control of its WeChat account while the call continued ringing, after which the compromised iPhone targeted another Android device. The worm spreads automatically between trusted contacts, functioning like a classic network worm but using WeChat profiles as propagation nodes. Even if the victim answers or declines the call, the exploit can persist or be retried, for example during nighttime hours. After account takeover, attackers gain full control to read and send messages, make calls, and impersonate the owner, while the underlying smartphone itself remains unaffected. Tencent received notification in July, released patches in versions 8.0.77 for Android and 8.0.76 for iOS, and server-side blocking was confirmed by late August, with no real-world attacks observed so far.