  Nowadays, mobile banking becomes a popular tool which consumers can conduct
financial transactions such as shopping, monitoring accounts balance,
transferring funds and other payments. Consumers dependency on mobile needs,
make people take a little bit more interest in mobile banking. The use of the
one-time password which is sent to the user mobile phone by short message
service (SMS) is a vulnerability which we want to solve with proposing a new
scheme called S-Mbank. We replace the authentication using the one-time
password with the contactless smart card to prevent attackers to use the
unencrypted message which is sent to the user's mobile phone. Moreover, it
deals vulnerability of spoofer to send an SMS pretending as a bank's server.
The contactless smart card is proposed because of its flexibility and security
which easier to bring in our wallet than the common passcode generators. The
replacement of SMS-based authentication with contactless smart card removes the
vulnerability of unauthorized users to act as a legitimate user to exploit the
mobile banking user's account. Besides that, we use public-private key pair and
PIN to provide two factors authentication and mutual authentication. We use
signcryption scheme to provide the efficiency of the computation. Pair based
text authentication is also proposed for the login process as a solution to
shoulder-surfing attack. We use Scyther tool to analyze the security of
authentication protocol in S-Mbank scheme. From the proposed scheme, we are
able to provide more security protection for mobile banking service.
