Secure Multi-Organization Cloud File Sharing Using Hybrid Cryptography and Blockchain Auditing

As the use of cloud-based collaboration platforms intensifies, securing file storage, controlled access, and their inability to be tampered with needs to be considered one of the key issues. The paper offers the architecture of a multi-organization file sharing system developed with the help of React to improve the front-end, AWS Cloud Services to support the backend with scalability, Hybrid Cryptography (AES-128-GCM + RSA) to ensure the data confidentiality, and the use of Blockchain to provide the immutability of audit.

The system allows the users to upload, store, share, and access files in a safe manner and they are part of various organizations. AWS Cognito is used to perform authentication and managing identities and AWS S3 offers an encrypted storage with isolation configuration per user. Malware analysis of files is performed with AWS Lambda which is connected to ClamAV before storage. AES-128-GCM is used to provide effective symmetric encryption and integrity-checking, but RSA is used to provide effective transfer of keys and controlled decryption. The blockchain is embedded to keep the logs of the key events like the login, upload, and file sharing ones tamper-proof.

Compared to other existing solutions, the proposed solution has better security measures, fine-crying access control, malware management, and trusted audit trails, and this renders it appropriate in collaboration settings within an enterprise.