Fix AES-256 to AES-128-CBC documentation accuracy

Co-authored-by: irfan-sec <[email protected]>

Author: Copilot

CHANGELOG.md

@@ -3,21 +3,21 @@
 ## [3.0.0] - 2026-02-26
 
 ### New Features
-- **🔒 AES-256 Encryption**: Optional password-based encryption for hidden messages using Fernet (AES-128-CBC + HMAC-SHA256) with PBKDF2 key derivation (600,000 iterations)
+- **🔒 AES Encryption**: Optional password-based encryption for hidden messages using Fernet (AES-128-CBC + HMAC-SHA256) with PBKDF2 key derivation (600,000 iterations)
 - **🖼️ BMP Image Support**: Added BMP format support for image steganography
 - **📋 Version Flag**: Added `-V`/`--version` CLI flag to display current version
 - **🔐 Crypto Module**: New `stegano/crypto.py` module with `encrypt_message()`, `decrypt_message()`, and `is_encrypted()` functions
 
 ### CLI Enhancements
-- **`-p`/`--password`**: New flag for encode and decode commands to enable AES-256 encryption/decryption
+- **`-p`/`--password`**: New flag for encode and decode commands to enable AES encryption/decryption
 - Automatic detection of encrypted messages during decoding with clear user prompts
 
 ### GUI Enhancements
 - **Password fields**: Added encryption password input to both Encode and Decode tabs
 - **BMP support**: Updated file dialogs to include BMP format
 
 ### Dependencies
-- **Added**: `cryptography>=42.0.4` for AES-256 encryption support
+- **Added**: `cryptography>=42.0.4` for AES encryption support
 
 ### Testing
 - **6 new tests**: Encryption/decryption cycles, wrong password handling, BMP format support, encrypted steganography end-to-end test

README.md

@@ -2,7 +2,7 @@
 
 **stegano-sec** is a Python-based, offline steganography toolkit for security enthusiasts, CTF players, and researchers. It allows you to hide (encode) and extract (decode) text or files within various media types—such as images (PNG, JPEG), audio (WAV), and plain text files—with no need for external APIs or internet access. The toolkit is designed to be modular, user-friendly, and easily extensible, making it ideal for both educational and practical infosec use.
 
-> **🆕 Version 3.0.0**: Now with AES-256 encryption, BMP support, and enhanced CLI!
+> **🆕 Version 3.0.0**: Now with AES encryption, BMP support, and enhanced CLI!
 
 ---
 
@@ -12,7 +12,7 @@
   - PNG, JPEG & BMP images (using LSB steganography)
   - WAV audio files (LSB steganography)
   - Plain text files (whitespace or zero-width character encoding)
-- **🔒 AES-256 Encryption**: Optional password-based encryption for hidden messages
+- **🔒 AES Encryption**: Optional password-based encryption for hidden messages
 - **Graphical User Interface (GUI)** - Easy-to-use tkinter-based interface
 - **Command-line interface (CLI)** for easy usage and scripting
 - **Modular codebase** for adding new media formats or encoding techniques
@@ -122,7 +122,7 @@ stegano-sec/
 │   ├── image.py           # Image steganography functions
 │   ├── audio.py           # Audio steganography functions
 │   ├── text.py            # Text steganography functions
-│   ├── crypto.py          # AES-256 encryption/decryption
+│   ├── crypto.py          # AES encryption/decryption
 │   └── utils.py           # Helper utilities
 ├── requirements.txt
 ├── README.md
@@ -171,20 +171,20 @@ pre-commit run --all-files
 
 ## What's New in v3.0.0
 
-- **🔒 AES-256 Encryption**: Password-based encryption using `--password` flag for both CLI and GUI
+- **🔒 AES Encryption**: Password-based encryption using `--password` flag for both CLI and GUI
 - **🖼️ BMP Support**: Added BMP image format for steganography
 - **📋 Version Flag**: Added `--version` / `-V` CLI flag
 - **🔐 Crypto Module**: New `stegano/crypto.py` with encrypt/decrypt/detect functions
 - **🧪 Expanded Tests**: 11 tests covering encryption, BMP support, and core functionality
-- **📦 New Dependency**: `cryptography` library for secure AES-256 encryption
+- **📦 New Dependency**: `cryptography` library for secure AES encryption
 
 All existing functionality remains fully compatible!
 
 ---
 
 ## Security Notice
 
-This toolkit is for educational and research purposes. While v3.0.0 adds AES-256 encryption for hidden messages, steganography alone does **not** provide strong security. The encryption feature adds a layer of protection, but do not rely solely on it for high-security scenarios in adversarial environments.
+This toolkit is for educational and research purposes. While v3.0.0 adds AES encryption for hidden messages, steganography alone does **not** provide strong security. The encryption feature adds a layer of protection, but do not rely solely on it for high-security scenarios in adversarial environments.
 
 ---
 

stegano/crypto.py

@@ -1,8 +1,9 @@
 """
 Cryptographic utilities for stegano-sec
 
-Provides password-based AES-256 encryption using Fernet (authenticated encryption)
-with PBKDF2 key derivation for securing hidden messages.
+Provides password-based authenticated encryption using Fernet
+(AES-128-CBC + HMAC-SHA256) with PBKDF2 key derivation for securing
+hidden messages.
 """
 
 import base64
@@ -40,11 +41,9 @@ def _derive_key(password: str, salt: bytes) -> bytes:
 
 
 def encrypt_message(message: str, password: str) -> str:
-    """Encrypt a message using AES-256 with a password.
+    """Encrypt a message with a password using authenticated encryption.
 
     Uses Fernet (AES-128-CBC with HMAC-SHA256) for authenticated encryption.
-    The salt is prepended to the ciphertext so decryption only needs the
-    password.
 
     Args:
         message: Plaintext message to encrypt

stegano_sec.py

@@ -295,7 +295,7 @@ def create_parser() -> argparse.ArgumentParser:
     encode_parser.add_argument(
         "-p",
         "--password",
-        help="Encrypt message with AES-256 using this password",
+        help="Encrypt message with AES using this password",
     )
 
     # Decode command

stegano_sec_gui.py

@@ -163,7 +163,7 @@ def setup_encode_tab(self) -> None:
             password_frame, textvariable=self.encode_password, show="*", width=30
         ).pack(side=tk.LEFT, padx=5)
         ttk.Label(
-            password_frame, text="(AES-256 encryption)", foreground="gray"
+            password_frame, text="(AES encryption)", foreground="gray"
         ).pack(side=tk.LEFT, padx=5)
 
         # Encode button