Android Dialer Vulnerability Enables One-Tap Call Forwarding Hijack

• •Vulnerability allows one-tap call forwarding hijack via MMI codes.
• •66 of 88 scanned apps with CALL_PHONE permission are affected.
• •Google classifies the issue as a third-party app problem.

A security researcher has demonstrated a vulnerability in Android dialer apps that allows attackers to silently execute MMI codes via a single tap on a web link. This exploit targets apps with the CALL_PHONE permission, enabling unauthorized call forwarding without user consent. The researcher, known as karansaini, found that 66 out of 88 scanned call and VoIP applications declared the CALL_PHONE permission, with 54 exposing browser-reachable dialer deeplinks. The exploit was confirmed on devices running Android 16 and an emulator for Android 17. Google has classified this issue as a third-party app problem rather than an OS vulnerability. The researcher reported that the attack could intercept important calls, including one-time passcodes and bank verification callbacks. The vulnerability poses significant risks to users with vulnerable dialer applications installed on their devices.