SecureBit.chat - P2P Encrypted Messenger Files

Version 4.5.22 — Advanced Cryptographic Core Update

Enhanced HKDF-Based Key Derivation

Major cryptographic upgrade implementing a modern, RFC 5869-compliant HKDF derivation process, ensuring stronger isolation and future-proof session key security.

Key Improvements:

• Implemented proper HKDF key derivation following RFC 5869
• Added Perfect Forward Secrecy (PFS) for enhanced session confidentiality
• Improved key separation via unique info parameters per derived key
• Increased salt entropy from 32 → 64 bytes
• Integrated ECDH + HKDF flow following Web Crypto API standards
• Introduced metadata encryption key for sensitive data protection
• Added structured error handling and validation logic
• Backward compatible with previous secure sessions

Security Enhancements

This release significantly strengthens the cryptographic infrastructure of SecureBit Chat:

• Cryptographic isolation between encryption, metadata, and handshake keys
• Enhanced protection against cross-key and future key compromise
• Improved compliance with OWASP cryptographic storage recommendations
• Alignment with RFC 7748 and NIST SP 800-56A standards
• Higher resistance to potential entropy degradation

Technical Details

• Refactored deriveSharedKeys() with HKDF-compliant key schedule
• Updated WebRTCManager to integrate the new messageKey API
• Enhanced validation and fallback error handling
• Standardized crypto operations across all supported browsers
• Improved logging and debugging for cryptographic lifecycle tracking

Architecture Overview

CryptoCore:

  - HKDF (RFC 5869) compliant derivation
  - ECDH ephemeral key exchange
  - Unique salt & info separation
  - Metadata encryption key layer
  - Automatic key validation
  - Structured error isolation

Browser Compatibility

• Chrome / Edge 90+ ✅
• Firefox 88+ ✅
• Safari 14+ ✅
• Opera 75+ ✅

Why This Update Matters

Version 4.4.99 establishes a new level of cryptographic robustness. By integrating Perfect Forward Secrecy and HKDF key derivation, SecureBit Chat achieves modern, standard-compliant, and future-ready encryption security — without sacrificing backward compatibility.