This paper looks at cyber security threats to cyber banking in South Africa. Cyber-attacks on information systems, especially financial systems have been a common phenomenon in recent times. This phenomenon has spurred financial institutions in South Africa to look at risk management as a crucial entity in their business model. Continuous investment in up-to-date security measures and technologies helps to prevent heavy financial and information loses that may be caused by cyber-attacks. The growth of cyber-crimes is becoming a serious economic issue to South African organizations in particular and the country as a whole. This paper begins by analyzing the various cyber threats involved in cyber banking. Secondly, it proposes a cyber-banking security architecture, with the boundary and application security. The boundary security architecture comprises of four components and the application security proposes strategies to avoid vulnerabilities. Lastly this paper proposes a cyber-banking security framework to be adopted by financial institutions.