WEWORM

Summary from the TLDR InfoSec newsletter

Calif has demonstrated a zero-click worm that takes over a WeChat account via an unanswered VoIP call, then uses that account to call the victim's contacts. This exploit relies on a memory corruption bug in WeChat's VoIP stack and requires the attacker to be on the victim's friend list, which is a weak barrier since one compromised friend can lead to further exploitation. Tencent has mitigated this issue in server-side updates and in client versions Android 8.0.77 and iOS 8.0.76, so users should enforce these updates and reconsider trusted-contact privileges in messaging apps.