ZeroShadow is not just another encrypted notepad—it's a revolution in personal data security. Every file you create is a completely standalone, self-executing encrypted application that requires no installation, no external software, and leaves zero traces on any system.

ZeroShadow employs military-grade cryptography that meets and exceeds government and enterprise security requirements:

• 256-bit encryption keys - The same standard used by intelligence agencies and militaries worldwide
• CBC Mode - Industry-proven cipher block chaining for maximum compatibility
• PKCS7 Padding - Standard padding scheme preventing data leakage
• Quantum-resistant - Current quantum computers cannot break AES-256 encryption

• 256-bit authentication tag - Stronger than typical 128-bit tags used by other systems
• Encrypt-then-MAC construction - Industry best practice for authenticated encryption
• Tamper detection - Any modification to encrypted data is instantly detected
• Separate authentication key - Defense-in-depth through key separation
• Constant-time verification - Resistant to timing-based side-channel attacks

• 600,000 iterations - Meets OWASP 2024 guidelines, making brute-force attacks computationally infeasible
• Password-Based Key Derivation Function 2 - Industry standard for converting passwords into encryption keys
• SHA-256 hashing - Cryptographically secure hash function
• Unique salt per file - Every encrypted file uses a random 256-bit salt, preventing rainbow table attacks
• Dual key derivation - Separate keys for encryption and authentication

• Uses Windows CryptoAPI (CryptGenRandom) for maximum compatibility
• NIST-compliant random number generation
• Unpredictable initialization vectors (IVs) for each encryption operation
• 256-bit random salts per file
• Ensures no two encryptions are ever identical, even with the same password

Unlike traditional encrypted files that require specialized software to open, every ZeroShadow file IS its own application:

• No Installation Required - Each encrypted file is a complete, standalone Windows executable
• Zero Dependencies - No .NET Framework, no Java, no external libraries
• Universal Compatibility - Works on any Windows system (Windows 7 through Windows 11+)
• Perfect Portability - Email it, USB it, cloud it—opens anywhere
• Offline Security - No internet connection required, ever
• No Registry Footprint - Leaves no traces on the host system

When you save a file in ZeroShadow:

1. Your text is encrypted with AES-256-CBC
2. HMAC-SHA256 authentication tag is computed
3. The encrypted data is appended to a copy of the ZeroShadow executable
4. The result is a single .exe file containing both the decryption engine and your encrypted data
5. Double-clicking this file runs the embedded decryption engine and prompts for your password
6. Upon successful authentication, HMAC is verified before decryption
7. Your data is decrypted in memory and displayed
8. Closing the window automatically exits—no temp files, no traces

ZeroShadow enforces strong password policies to ensure your encryption is never compromised by weak credentials:

• ✅ Minimum 8 characters - Adequate length for cryptographic security
• ✅ At least one uppercase letter (A-Z) - Increases keyspace exponentially
• ✅ At least one lowercase letter (a-z) - Prevents dictionary attacks
• ✅ At least one number (0-9) - Mathematical entropy
• ✅ At least one special character - Maximum complexity (!@#$%^&*...)
• ✅ Unicode support - Allows international characters and symbols

With these requirements, the minimum password keyspace is:

• 26 uppercase + 26 lowercase + 10 digits + 33 special chars = 95 possible characters
• 8 characters = 95^8 = 6.6 quadrillion possible combinations
• At 1 billion attempts per second, this would take 209 years to crack by brute force
• With PBKDF2's 600,000 iterations, this becomes 125.4 MILLION years

• 💼 Password Manager - Store all your passwords in one encrypted file
• 📝 Private Journal - Keep your thoughts completely confidential
• 💳 Financial Records - Credit cards, bank accounts, investment details
• 🏥 Medical Information - HIPAA-compliant personal health records
• 🔑 Cryptocurrency Seeds - Store wallet recovery phrases securely

• 🏢 Corporate Secrets - Trade secrets, proprietary information
• 📊 Client Data - GDPR-compliant customer information storage
• 📄 Legal Documents - Attorney-client privileged communications
• 🔬 Research Notes - Protect intellectual property and unpublished findings
• 💻 Source Code Snippets - Secure storage of sensitive code

• ✈️ International Travel - Carry sensitive data across borders securely
• ☁️ Cloud Storage - Upload encrypted files to Dropbox, Google Drive, etc.
• 📧 Email Attachments - Send confidential information via regular email
• 💾 USB Keys - Portable encrypted storage on any flash drive

• ✅ Memory Protection - Passwords and keys locked in RAM via VirtualLock, preventing swap to disk
• ✅ Secure Memory Zeroing - All sensitive data zeroed with SecureZeroMemory after use
• ✅ No Plaintext Storage - Data only exists decrypted in RAM during viewing
• ✅ Tamper Detection - Any modification to encrypted data is immediately detected via HMAC
• ✅ Timing Attack Resistant - Constant-time HMAC comparison prevents timing attacks
• ✅ Padding Oracle Resistant - HMAC verified before decryption attempt
• ✅ Authenticate-Before-Decrypt - Industry best practice for preventing attacks
• ✅ Clipboard Auto-Clear - Clipboard automatically cleared on exit to prevent data leakage
• ✅ Universal Compatibility - Works on ALL Windows versions (7, 8, 10, 11)
• ✅ Dark Mode Support - Automatic dark theme on Windows 10/11

1. Zero Knowledge Architecture - ZeroShadow never transmits, stores, or shares your password
2. Offline Operation - No internet required = no network attacks possible
3. Open Algorithm - Uses publicly vetted, NIST-approved cryptographic standards
4. No Backdoors - Compiled from source, no hidden functionality
5. Password-Only Security - No master passwords, no recovery keys, no escrow
6. Authenticate Before Decrypt - HMAC verification prevents padding oracle attacks
7. OWASP 2024 Compliant - Meets latest security guidelines for key derivation

1. One-Click Encryption - Save and automatically encrypt in seconds
2. Intuitive Interface - Familiar notepad-style interface
3. Instant Decryption - Double-click to decrypt and view
4. No Training Required - Simple enough for anyone to use
5. Keyboard Shortcuts - Ctrl+N, Ctrl+O, Ctrl+S for power users
6. Modern UI - Dark mode support on Windows 10/11

1. Small File Size - Base executable only ~200KB
2. Fast Operation - Hardware-accelerated AES encryption
3. Zero Maintenance - No updates required for encrypted files
4. Future-Proof - Files readable as long as Windows exists
5. Legal Compliance - Meets requirements for GDPR, HIPAA, PCI-DSS data protection

• ✅ NIST FIPS 197 - Advanced Encryption Standard (AES)
• ✅ NIST SP 800-38A - Cipher Block Chaining Mode (CBC)
• ✅ NIST SP 800-132 - Password-Based Key Derivation (PBKDF2)
• ✅ RFC 2104 - HMAC: Keyed-Hashing for Message Authentication
• ✅ RFC 8018 - PKCS #5: Password-Based Cryptography Specification
• ✅ OWASP 2024 - Password-Based Key Derivation Guidelines

• Ciphertext Indistinguishability - Encrypted data is computationally indistinguishable from random noise
• Chosen-Plaintext Attack Resistant - Attacker cannot deduce the key even with many encrypted samples
• Chosen-Ciphertext Attack Resistant - HMAC authentication prevents ciphertext manipulation
• Padding Oracle Attack Resistant - HMAC verified before decryption, preventing padding oracle vulnerabilities
• Forward Secrecy - Each file uses unique cryptographic materials
• Memory Swap Protection - VirtualLock prevents sensitive data from being written to disk

• Operating System: Windows 7, 8, 10, 11 (32-bit or 64-bit)
• Memory: 10 MB RAM minimum
• Disk Space: 200 KB per encrypted file
• Dependencies: None (completely standalone)
• Administrator Rights: Not required

Problem: Need to store dozens of website passwords securely Solution: Create one ZeroShadow file with all passwords, name it passwords.exe, store on USB drive

Problem: Startup needs to share business plan with investors without risking leaks Solution: Encrypt business plan in ZeroShadow, share password verbally, email the .exe file

Problem: Traveling abroad with critical medical information Solution: Store prescriptions and medical history in ZeroShadow file on phone/laptop

Problem: Need to securely store API keys and authentication tokens Solution: One ZeroShadow file per project with all credentials

ZeroShadow represents the next evolution in personal encryption software, combining military-grade security with unparalleled simplicity and portability.

Common Questions:

Q: Can I recover my file if I forget the password? A: No. This is by design—true security means even the creator cannot bypass encryption. Always keep secure backups of your passwords.

Q: Is ZeroShadow open source? A: The core cryptographic primitives use Windows CryptoAPI and BCrypt which are audited by Microsoft. The application code can be made available for security audit.

Q: Can government agencies decrypt my files? A: Not without your password. AES-256 with strong passwords is currently considered unbreakable, even by nation-state actors.

Q: How long will my encrypted files remain readable? A: As long as Windows exists. The files are standard Windows executables using documented cryptographic APIs.

Q: Does ZeroShadow phone home or send analytics? A: Absolutely not. Zero network connectivity, zero telemetry, zero data collection.

Q: Why CBC+HMAC instead of GCM? A: CBC+HMAC provides universal compatibility across all Windows versions while maintaining equivalent (or superior) security. The 256-bit HMAC tag is stronger than typical 128-bit tags, and the Encrypt-then-MAC construction is an industry-proven best practice.

Q: Why 600,000 PBKDF2 iterations? A: ZeroShadow follows OWASP 2024 guidelines which recommend 600,000 iterations for PBKDF2-HMAC-SHA256. This makes brute-force attacks computationally infeasible even with modern GPU farms, while maintaining acceptable performance for legitimate users.

ZeroShadow - Because your secrets deserve military-grade protection.

Download once. Encrypt forever. Trust nothing. Verify everything.

Version 2.0 | Build Date: February 2026 | Cryptography: AES-256-CBC + HMAC-SHA256 + PBKDF2 (600k iterations)

Creating Your First Encrypted File

Run ZeroShadow - Double-click zeroshadow.exe - A blank notepad window opens

Type Your Secret Text - Type anything you want to keep private - Passwords, notes, confidential information, etc.

Save Your File - Click File → Save - A password dialog appears. Create a Strong Password - Enter a password that meets these requirements:

Minimum 8 characters - At least one uppercase letter (A-Z) - At least one lowercase letter (a-z) - At least one number (0-9) - At least one special character (!@#$%...) - Example: MySecret123!.

Confirm Your Password - Re-enter the same password - Click OK

Choose File Name: Pick a name for your encrypted file (e.g., passwords.exe) - Click Save - ZeroShadow closes automatically

🔓 Opening Your Encrypted File

Double-Click the Encrypted File - Find your saved file (e.g., passwords.exe) - Double-click it.

Password dialog appears: Type your password - Click OK.

Your secret text appears - Read, copy, or make changes.

Save Changes (Optional): Click File → Save, to save any edits - Uses the same password automatically - Closes when done