This repository contains an improved and secured version of a simplified web-based password manager. The project was developed in the context of a university assignment on Aristotle's University of Thessaloniki(AUTh) Information Systems Security class. The original application intentionally contained multiple security vulnerabilities. The purpose of this work was to identify, analyze, and mitigate these vulnerabilities using well-established security practices.

The application is implemented in PHP and uses a MySQL database for data storage. The deployment is fully containerized using Docker and Docker Compose, ensuring reproducibility and ease of execution across different operating systems.

Architecture Overview

The application is deployed as a multi-container system. Each component has a clearly defined role and responsibility. All services are isolated and communicate only through Docker-managed networks.

Components

Web Application (PHP)

The web service hosts the PHP-based password manager application. It is responsible for:

User authentication and session handling
Secure storage and retrieval of credentials
Input validation and output sanitization
Interaction with the database through restricted credentials

The PHP application runs inside its own container and does not expose any ports directly to the host system.

Database (MySQL)

The database service provides persistent storage for:

User accounts
Stored credentials
Application data

Security improvements include:

Use of a dedicated database user with limited privileges
Separation of database credentials via environment variables
Isolation of the database service from direct external access

Reverse Proxy and HTTPS (Caddy)

Caddy is used as a reverse proxy in front of the web application. It provides:

Automatic HTTP to HTTPS redirection
Internal TLS certificate generation
Secure termination of HTTPS connections
Optional security-related HTTP headers

All external access to the application is handled exclusively by Caddy.

Deployment Instructions

The deployment process is identical for Linux and Windows. The only requirement is a working Docker installation.

Prerequisites

Docker
Docker Compose (included in modern Docker installations)

No additional software such as Apache, PHP, or MySQL is required on the host system.

Deployment on Linux

Open a terminal.
Navigate to the project directory containing docker-compose.yml.
Run the following command:
```
docker compose up -d --build
```
Wait until all containers are built and started.
Access the application through your browser using: https://localhost

Deployment on Windows

Install Docker Desktop for Windows.
Ensure that WSL2 is enabled (Docker Desktop will guide you automatically).
Open PowerShell or Command Prompt.
Navigate to the project directory containing docker-compose.yml.
Run the following command:
```
docker compose up -d --build
```
Once the containers are running, open a browser and navigate to: https://localhost

Notes on Reproducibility

The use of Docker ensures that:

The application behaves identically on all supported operating systems
No manual configuration of web servers or databases is required
Environment-specific issues are minimized

This approach allows evaluators to focus on the security aspects of the application rather than deployment complexity.

Disclaimer

This project was developed solely for educational purposes. It is provided "as is", without any express or implied warranties. The author assumes no responsibility for any misuse, data loss, security incidents, or damages resulting from the use of this software. This implementation should not be used in production environments.

All work, modifications, and security improvements are the sole responsibility of the author.