Abstract:

SMS has become a common used method in twofactor authentication, which is widely used for website login, mobile payment, bank transfer and other critical applications. However, many malicious applications take use of mobile operating system vulnerabilities to eavesdrop and intercept SMS for users’ authentication code, which brings a great threat on the security of the user’s property. To defend such malicious applications, many SMS encryption applications based on symmetric key encryption algorithm or public/private key system have been started using, which bring great convenience to the users. However, such solutions cannot guarantee the confidentiality of the SMS plaintext or even the seeds when the mobile OS is compromised. This paper presents TrustSMS(Trusted Short Message Service), a secure SMS encryption scheme by using ARM TrustZone technology. TrustSMS can not only protect the confidentiality of the SMS against a malicious mobile OS, but also guarantee reliable end-to-end SMS transmission. A prototype of TrustSMS is developed on Samsung Exynos 4412. The experimental results show that TrustSMS has small impacts on the mobile OS and its performance overhead is less than 1%.

Key words:

text-indent: 21pt">SMS encryption, ARM TrustZone technology, NTRU publicmso-ascii-font-family: 'Times New Roman', mso-hansi-font-family: 'Times New Roman'">key cryptosystem, mobile security