In the Twilio Authy API, accessed by Authy Android before 25.1.0 and Authy iOS before 26.1.0, an unauthenticated endpoint provided access to certain phone-number data, as exploited in the wild in June 2024. Specifically, the endpoint accepted a stream of requests containing phone numbers, and responded with information about whether each phone number was registered with Authy. (Authy accounts were not compromised, however.)

A race condition in the Twilio Authy 2-Factor Authentication application before 24.3.7 for Android allows a user to potentially approve/deny an access request prior to unlocking the application with a PIN on older Android devices (effectively bypassing the PIN requirement).