EntropyX Core Advanced Compression

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 EntropyX: Core implements comprehensive security controls designed to protect data integrity and ensure safe file processing. The following technical features are built into the application:

File Processing Security:

• File Type Validation: Strict whitelist of 20+ supported extensions
• Size Limits: 500MB maximum per file enforced before processing
• Path Sanitization: Automatic removal of dangerous characters and path traversal prevention
• Reserved Name Protection: Windows system name blocking (CON, PRN, AUX, NUL, COM1-9, LPT1-9)
• Input Validation: Real-time filename sanitization with dangerous character filtering
• Symlink Detection: Active detection and blocking of symbolic links with security event logging
• Path Length Limits: 260-character maximum path length and 200-character filename limit
• Real-path Verification: Resolution and validation of actual filesystem paths against parent directory boundaries

Encryption & Data Protection:

• Algorithm: Fernet (symmetric encryption) when cryptography library available
• Secure Key Storage: Keys stored in ~/.entropyx/encryption.key with restricted permissions (0700 directory, 0600 file on Unix)
• Integrity Verification: SHA-256 checksums for files under 10MB
• Session Tracking: UUID-based session IDs for all operations
• Build Identification: Static build ID (AngeloF799617-SEC) for version tracking

Command Execution Security:

• Injection Protection: List-based command execution with shell=False for all subprocess calls
• Argument Validation: Maximum 100 arguments with dangerous character blocking (&, |, ;, $, `, etc.)
• Timeout Enforcement: Configurable timeouts (default 60s for commands, 300s for media operations)
• Environment Sanitization: Removal of dangerous environment variables (LD_PRELOAD, LD_LIBRARY_PATH, DYLD_INSERT_LIBRARIES)
• Executable Verification: Path resolution and symlink checking for all executables
• PowerShell Sandboxing: ExecutionPolicy Bypass with controlled script execution for DOCX conversion

Comprehensive Audit System:

• Dual Logging: Full debug logs (10MB rotation, 10 files) and audit logs (daily rotation, 30-day retention)
• Structured Logging: JSON-formatted operation logs with metadata
• Integrity Protection: SHA-256 hash on each log entry for tamper detection
• Event Categories: FILE_OPERATION, COMPRESSION_RESULT, SECURITY_EVENT, ERROR_TRACE classifications
• Security Monitoring: Real-time logging of PATH_TRAVERSAL_ATTEMPT, SYMLINK_ESCAPE, FILE_TOO_LARGE, INVALID_PATH events
• Traceability: Complete operation tracking with timestamps, user info, and session correlation

Application Security:

• Resource Limits: Maximum 5 concurrent operations with system resource monitoring
• Memory Protection: 80% memory usage threshold with automatic operation blocking
• Cleanup Handlers: Automatic temporary file cleanup on exit with signal handlers (SIGINT, SIGTERM)
• Error Handling: Sanitized error messages with full traceback logging to secure logs only
• Thread Safety: Operation locking for concurrent task management
• Process Monitoring: Real-time CPU and memory usage tracking with PSUtil (when available)

EntropyX: Core is engineered to align with leading industry security and privacy frameworks. The following controls are implemented to support compliance across major standards:

OWASP Top Ten:

• Input Validation: Strict file type validation using extension whitelist for 20+ supported formats
• Path Traversal Prevention: Pattern detection for ../, ..\, and multiple regex-based dangerous path patterns
• File Size Controls: 500MB maximum file size with enforcement before processing
• Filename Sanitization: Removal of dangerous characters and Windows reserved names (CON, PRN, AUX, NUL, COM1-9, LPT1-9)
• Secure File Handling: Real path resolution, symlink detection, and parent directory boundary enforcement
• Encryption Protection: Fernet encryption (when available) with secure key storage
• Security Logging: Built-in security event monitoring with SHA-256 integrity hashing on all log entries
• Error Handling: Sanitized error messages with full details logged securely

NIST Cybersecurity Framework:

• Identify: Static build identification (AngeloF799617-SEC) for version tracking
• Protect: File processing security with encryption, validation, and subprocess sandboxing
• Detect: Real-time security event monitoring with dual logging system
• Respond: Automated error handling with JSON-structured event logging and session correlation
• Recover: Signal handler-based cleanup procedures with automatic temporary file removal

ISO 27001 Controls:

• A.12 Operations Security: Dual logging system with rotation policies and secure subprocess execution
• A.10 Cryptography: Fernet encryption with file-based key storage and permission restrictions
• A.14 System Acquisition: Secure subprocess wrapper with timeout enforcement and argument validation
• A.16 Incident Management: Security event categories (PATH_TRAVERSAL_ATTEMPT, SYMLINK_ESCAPE, FILE_TOO_LARGE)
• A.18 Compliance: 30-day audit trail retention with daily rotation and integrity protection

HIPAA and PCI DSS:

• Technical Safeguards: File encryption capability, path validation, and comprehensive audit logging
• Data Protection: Fernet encryption for sensitive files with SHA-256 integrity verification for small files
• Audit Requirements: JSON-structured logging of all file operations with user and session tracking
• Access Controls: File type restrictions, size limits, and dangerous character filtering

SOC 2 and SOX:

• Operational Controls: Timestamped audit trails of all file processing and compression operations
• Internal Controls: Resource monitoring with concurrent operation limits and memory thresholds
• Transparency: Dual logging system supporting operational review with 10MB/30-day retention
• Review Support: SHA-256 integrity hashing on each log entry for tamper detection

Data Protection Regulations:

• GDPR Article 32: Security of processing through local-only file handling with no network transmission
• CCPA Technical Safeguards: Privacy-by-design with all processing performed locally on user's system
• Privacy by Design: No external API calls, telemetry, or data collection beyond local logging
• Data Minimization: Only essential file metadata logged with automatic cleanup via atexit handlers

Please note: While EntropyX Core includes foundational security and privacy features supporting these frameworks, full compliance requires additional organizational controls including user authentication, network isolation, log management systems, and administrative procedures specific to your deployment environment.