Securing the information from the attackers is a crucial aspect of modern digital life. Numerous cryptographic algorithms are employed to provide security for data transmission. Among these, the International Data Encryption Algorithm (IDEA) stands out as a widely utilized algorithm for enhancing security. However, the IDEA algorithm has a notable drawback due to its relatively large number of weak keys. This susceptibility stems from the fixed 25-bit circular left shift during each key generation round. It is made weakens the regular key generation process of the IDEA algorithm. To address these concerns, this research work introduces a Modified International Data Encryption Algorithm (MIDEA) using a key size of 1024 bits. The method suggests a novel approach for the circular left shift by employing different bits that effectively overcome the limitations of fixed bits of the circular left shift. Additionally, this work presented innovative encryption and decryption techniques using a key size of 1024 bits. A comprehensive comparison is conducted between the IDEA and the MIDEA algorithm based on time complexity and security. Furthermore, this work provides a novel phishing attack detection framework using the suggested MIDEA technique. This framework is used for securely sharing patient data in the healthcare sector. The results of the proposed work indicate that encryption time varied from 20.08930 to 494.18258 seconds across file sizes from 0.97 to 40.8 megabytes. The experimental results demonstrate that the MIDEA algorithm exhibits significant performance enhancements with encryption speed improved by 60.67 percent and decryption robustness by 63.24 percent.