Security Analysis of Mobile Authenticator Applications

Ozkan C., Bicakci K.

International Conference on Information Security and Cryptology (ISCTURKEY), ELECTR NETWORK, 3 - 04 Aralık 2020, ss.18-30 identifier identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Doi Numarası: 10.1109/iscturkey51113.2020.9308020
  • Basıldığı Ülke: ELECTR NETWORK
  • Sayfa Sayıları: ss.18-30
  • Anahtar Kelimeler: Android, Mobile Security, Reverse Engineering, Obfuscation, Cryptographic Controls, ProGuard, Android Key Store, Mobile Authenticator, Authentication, Two Factor Authentication
  • İstanbul Teknik Üniversitesi Adresli: Evet

Özet

Deploying Two-Factor Authentication (2FA) is one of the highly-recommended security mechanism against account hijacking attacks. One of the common methods for 2FA is to bring something you know and something you have factors together. For the latter we have options including USB sticks, smart cards, SMS verification, and one-time password values generated by mobile applications (soft OTP). Due to the cost and convenience reasons, deploying 2FA via soft OTPs is more common. However, unlike smart cards which have tamper resistance property, attackers can access smartphones remotely or physically so that they can fetch shared secret seed value - an important security risk for mobile authenticators. For this reason, it is critical to analyze mobile authenticator applications in this context. In this paper, we report our findings after analyzing eleven different Android authenticator applications. We report that we have fetched cleartext shared secret seed value from storage in five applications and from memory in seven applications using standard reverse engineering techniques and open-source tools.