Mobile Cloud Computing

The exponential rise of digital communication has intensified the need for security mechanisms capable of safeguarding sensitive data from interception, tampering, and unauthorized inference. Traditional cryptographic techniques protect content but often reveal the existence of protected information, attracting malicious attention. This paper presents SecureStegano, a privacy-preserving, multi- layer secure communication system that integrates SM4 encryption, dual steganography, blockchain-based audit logging, and real-time monitoring. The proposed architecture conceals both text and image data within carrier images using optimized LSB-based embedding, while SM4 encryption ensures confidentiality even if embedded data is extracted. A private blockchain maintains immutable, tamper-proof logs of cryptographic events, improving transparency and accountability. Experimental evaluations demonstrate that SecureStegano achieves strong imperceptibility, low overhead, robust security, and real- time alerting capabilities, making it suitable for critical sectors including defense intelligence, healthcare, finance, and secure personal communication.