Ruby on Rails Security Guide Protecting Your Business and Customer Data

Ruby on Rails Security Guide: Protecting Your Business and Customer Data

18 min read


Resistance to security threats is one of the key features for web projects, especially if your business belongs to one of those industries that has to comply with strict security regulations. When upgrading an existing Ruby on Rails product or planning a new one within this technology stack, it’s natural that you want to understand what security mechanisms you can implement to protect your business and customer data.

In this guide, we will delve into built-in Ruby on Rails security features, recommended practices for secure coding, and the availability of security-focused gems. This will help you set the right requirements for your development team and build secure RoR web applications. 

When to Assess the Security of Your Ruby on Rails Application 

While building secure web applications from the ground up is crucial, it is equally important to periodically assess the security of existing Ruby on Rails applications. Regular security assessments help identify potential RoR vulnerabilities, ensure compliance with security standards, and maintain a strong security posture. 

Here are the key indicators that suggest it is time to assess the security of your Ruby on Rails application.

  1. Changes in the Application’s Environment: If your application has undergone significant changes, such as Ruby on Rails app modernization, integration of new third-party libraries, or modifications to the infrastructure, it is advisable to conduct a security assessment. These changes can introduce new risks and vulnerabilities that need to be identified and addressed promptly.
  2. Integration of New Features or Functionality: When adding new features or functionality to your Ruby on Rails application, it is essential to assess the security implications of these additions. New features may introduce new attack vectors or potential weaknesses that could be exploited by malicious actors. 
  3. Compliance Requirements: If your business operates in a regulated industry or is subject to compliance standards such as GDPR, HIPAA, or PCI DSS, regular security assessments are necessary to ensure adherence to these requirements. This help identify any gaps in compliance and provide recommendations for remediation. Changes in regulations or industry security standards may also require a reassessment of your application’s security. 
  4. Security Incident or Breach: If your application has experienced a security incident or breach, it is crucial to conduct a thorough security assessment. This helps identify the root cause of the incident, determine the extent of the compromise, and implement appropriate remediation measures to prevent future incidents.
  5. Increase in User Base or Data Sensitivity: As your user base grows or the sensitivity of the data processed by your application increases, the security risks also escalate. Conducting periodic security assessments helps ensure that your application can handle the increased load securely and protect sensitive user information effectively.
  6. Vulnerability Reports or Threat Intelligence: If your app relies on third-party libraries or dependencies, it is essential to stay updated on any vulnerability reports associated with those components. 

Regular security assessments provide assurance that your application is resilient against emerging threats and instills confidence in your customers that their data is protected.

Built-in Security Features of Ruby on Rails 

Ruby on Rails is well known for its robustness and commitment to security. The framework incorporates several built-in security features that help protect web applications against common vulnerabilities. Understanding these features is crucial for developers and business owners to leverage the framework’s inherent security capabilities effectively.

1. Protection Against Cross-Site Scripting (XSS)

Cross-Site Scripting (XSS) is a prevalent attack vector that allows malicious actors to inject malicious scripts into web pages viewed by other users. 

Ruby on Rails addresses this vulnerability by automatically escaping user-generated content. When data is rendered in views, Ruby on Rails applies appropriate encoding to ensure that any potentially malicious scripts are displayed as plain text, effectively mitigating the risk of XSS attacks.

2. Prevention of Cross-Site Request Forgery (CSRF)

Cross-Site Request Forgery (CSRF) attacks exploit the trust between a web application and its users by tricking users into performing unintended actions on their behalf. 

Ruby on Rails protects against CSRF attacks by generating authenticity tokens and including them in forms and AJAX requests. When a user submits a form or performs an AJAX request, Ruby on Rails verifies the authenticity of the request using the token and prevents unauthorized actions.

3. Guarding Against SQL Injection Attacks

SQL injection attacks occur when an attacker inserts malicious SQL statements into input fields, leading to unauthorized access to, or manipulation of, the application’s database. 

Ruby on Rails guards against SQL injection attacks by utilizing parameterized queries. Parameters are passed separately from the SQL statement and ensure that user input is treated as data rather than executable code. 

4. Secure Session Management

Session management is crucial for maintaining user sessions securely. Ruby on Rails handles this by storing session data on the server-side, reducing the risk of sensitive session information being exposed. Additionally, session cookies are set to be secure by default, so they are only transmitted over encrypted channels (HTTPS).

5. Secure Cookie Handling

Ruby on Rails provides secure cookie handling by enabling the secure and httponly flags by default. The secure flag ensures that cookies are only transmitted over HTTPS. The httponly flag prevents client-side scripts from accessing the cookies, protecting them against theft through cross-site scripting attacks.

6. Password Encryption

Ruby on Rails incorporates a secure password encryption mechanism known as bcrypt. Bcrypt is a widely recognized and robust encryption algorithm that adds an extra layer of protection to user passwords. It employs a salted hashing technique that makes it computationally expensive for attackers to crack hashed passwords.

While Ruby on Rails is a secure technology by default, it is still the responsibility of developers and businesses to understand and address additional security considerations specific to their application, such as data encryption, user authentication, and authorization mechanisms beyond the built-in features. Following secure coding practices is one of the key way to achieve this. 

Secure Coding Practices in Ruby on Rails 

Secure coding practices are essential to building robust and secure web applications in Ruby on Rails. They help mitigate vulnerabilities and reduce the risk of attacks, facilitate early vulnerability detection, protect user data, safeguard business reputation, encourage continuous improvement as well as minimize the effort and cost required to fix security issues later.

At MobiDev, we follow official Ruby on Rails security guidelines and combine them with our own experience to solve complex security tasks faster and more efficiently. Let’s look at some secure coding practices in more detail.

  • Input Validation and Sanitization

Proper input validation is crucial to prevent attacks such as Cross-Site Scripting (XSS) and SQL injection. Ruby on Rails provides numerous validation helpers and sanitization methods to ensure that user input is validated and sanitized before being processed or displayed. Developers should validate and sanitize all user-provided data, including form inputs, query parameters, and URL components, to protect against malicious input and data manipulation.

  • Authentication and Authorization

Implementing secure authentication and authorization mechanisms is vital for controlling access to sensitive resources within the application. Ruby on Rails offers a comprehensive authentication framework called Devise, which simplifies the implementation of user authentication features. 

Devise provides secure password storage, password reset functionality, and account lockouts to protect against brute-force attacks. Additionally, developers should implement proper authorization mechanisms, such as role-based access control (RBAC) or attribute-based access control (ABAC), to ensure that users have the appropriate permissions to access specific resources and actions.

  • Session Management and Cookie Security

Ruby on Rails provides session management functionality by default. However, it is crucial to ensure that session data is stored securely on the server-side, rather than being stored in client-side cookies. Storing session data on the server side reduces the risk of disclosure or tampering of sensitive information.

  • Secure Password Handling

Passwords are a crucial component of user authentication and should be handled securely. When storing user passwords, developers should ensure that passwords are hashed using bcrypt with a unique salt for each user. This makes it computationally expensive for attackers to crack hashed passwords, even if the hashed password database is compromised.

  • Secure Data Handling

Sensitive data, such as personally identifiable information (PII) and financial information, should be handled with care. Developers should ensure that sensitive data is encrypted both in transit and at rest. This includes using HTTPS for secure communication between the application and clients, and employing encryption techniques, such as AES, for storing sensitive data in the application’s database. Encryption keys should be securely managed, and access to sensitive data should be restricted to authorized personnel.

  • Protection Against Cross-Site Scripting (XSS)

While Ruby on Rails provides automatic escaping of user-generated content, it is essential to understand the different types of XSS attacks and apply the appropriate countermeasures. Developers should be aware of the contexts where user input is displayed and use proper sanitization methods to prevent unintended execution of scripts.

  • Security Testing

Developers should conduct thorough security assessments, including penetration testing and vulnerability scanning, to identify potential weaknesses. Automated testing with tools such as Brakeman can be used to perform static code analysis and detect common security vulnerabilities. Additionally, manual code reviews and security audits should be conducted to identify any security flaws that automated tools may miss.

  • Regular Updates and Patching

Keeping the Ruby on Rails framework and its dependencies up to date is vital to address any security vulnerabilities that may arise. Developers should regularly check for updates and security patches and promptly apply them to the application. This includes updating the Ruby on Rails gem, as well as other gems and libraries used within the application.

Leveraging Security-Focused Gems in Ruby on Rails 

Ruby on Rails offers a vibrant ecosystem of gems that can be leveraged to enhance the security of web applications. These security-focused gems provide additional layers of protection and simplify the implementation of common security measures. 

Let’s explore some of the essential security-focused gems that can be used in Ruby on Rails development.

  1. Brakeman: It scans the application’s codebase to detect potential security vulnerabilities, including SQL injection, Cross-Site Scripting (XSS), and mass assignment vulnerabilities. Brakeman provides detailed reports highlighting the identified issues and recommendations for remediation as well as catches security vulnerabilities early in the development process.
  2. SecureHeaders: SecureHeaders simplifies the configuration and management of security-related HTTP headers, such as Content Security Policy (CSP), Strict Transport Security (HSTS), and X-XSS-Protection. By setting up appropriate headers, developers can mitigate various attack vectors, such as XSS attacks, clickjacking, and man-in-the-middle attacks. 
  3. Rack::Attack: Rack::Attack helps protect against brute-force attacks, DDoS attacks, and other types of abuse. With Rack::Attack, developers can define custom rules to limit the number of requests per IP address, block specific IP addresses or user agents, and configure protection strategies based on various conditions. This adds an extra layer of defense to RoR applications and prevents abuse or unauthorized access.
  4. Pwned: This tool integrates with the “Have I Been Pwned” service, which allows developers to check if user passwords or email addresses have been compromised in known data breaches. By leveraging Pwned, developers can implement proactive measures to enhance the security of user accounts. 
  5. strong_password: strong_password gem provides a validation mechanism that ensures passwords meet specific complexity criteria, such as minimum length, inclusion of uppercase letters, lowercase letters, numbers, and special characters. By incorporating strong_password, developers can reduce the risk of password-related vulnerabilities.
  6. Bullet: While it is not a security-specific gem, it can indirectly contribute to security by detecting potential performance issues and eager loading opportunities. By optimizing database queries, developers can mitigate the risk of certain security vulnerabilities, such as SQL injection and denial-of-service attacks. Bullet provides real-time suggestions for query improvements.
  7. Clearance: This lightweight authentication gem for Ruby on Rails apps simplifies the implementation of user authentication features while adhering to secure coding practices. Clearance handles password storage securely, uses bcrypt for password encryption, and provides features like account confirmation, password reset, and session management. 
  8. CanCanCan: CanCanCan simplifies role-based access control (RBAC) in Ruby on Rails applications. It enables developers to define user roles and permissions and easily enforce access controls based on these roles.

These security-focused gems provide valuable tools for developers to enhance the security posture of Ruby on Rails applications. However, it is essential to stay informed about updates and security patches for these gems and promptly apply them to maintain a secure environment. Additionally, developers should carefully review the documentation and best practices associated with each gem to ensure they are configured correctly and utilized effectively.

It’s also important to note that while these gems can assist in addressing common security concerns, they do not provide a comprehensive solution. Developers should always follow secure coding practices, conduct thorough security testing, and remain vigilant about emerging security threats to build and maintain secure web applications.

Serhii Koba

Ruby Group Leader

How to Secure APIs in Ruby on Rails

Securing APIs is a critical aspect of web application development, and Ruby on Rails provides robust features and tools to ensure this. APIs act as the bridge between different systems, allowing them to communicate and exchange data. At the same time, they can also be a target for attackers seeking to exploit vulnerabilities and gain unauthorized access to sensitive information. 

Below, you’ll find the key practices to protect your Ruby on Rail APIs against potential threats.

1. Authentication

Ruby on Rails offers various authentication mechanisms, such as token-based authentication and OAuth, that can be leveraged to secure APIs. Token-based authentication involves generating and validating tokens for each request, while OAuth provides a standardized framework for delegating authentication to third-party services. 

Developers should carefully choose the appropriate authentication mechanism based on their requirements and ensure that credentials are transmitted securely over encrypted channels (HTTPS).

2. Authorization

Once a user or application is authenticated, it’s crucial to implement authorization mechanisms to control access to specific resources and actions within the API. Above-mentioned Ruby on Rails libraries such as CanCanCan and Pundit enable developers to define granular access control rules based on user roles or permissions. 

It is important to thoroughly review and test the authorization logic to prevent unauthorized access to sensitive data or functionality.

3. API Key Management

Ruby on Rails provides mechanisms to generate and manage API keys. Developers should ensure that API keys are securely stored and transmitted using best practices such as encryption and secure key management. It is also crucial to implement mechanisms to revoke or regenerate API keys if they are compromised or no longer needed.

4. Input Validation and Sanitization

Similar to web applications, input validation and sanitization are crucial for APIs to prevent common security vulnerabilities such as SQL injection and Cross-Site Scripting (XSS). Developers should validate and sanitize all user-provided data, including query parameters and request payloads, to prevent malicious input and data manipulation. Ruby on Rails provides built-in validation and sanitization methods that should be utilized consistently throughout the API implementation.

5. Rate Limiting and Throttling

To protect APIs from abuse and potential denial-of-service attacks, rate limiting and throttling mechanisms can be implemented. Ruby on Rails provides middleware and gems like Rack::Attack that enable developers to define rate-limiting rules based on IP addresses, request types, or specific endpoints. These mechanisms help prevent excessive API requests and ensure fair usage of API resources.

6. Secure Error Handling

Error handling is an often overlooked aspect of API security. But it is crucial to avoid exposing sensitive information or providing attackers with valuable insights into the API’s internals. Developers should implement a consistent error handling mechanism that provides informative, but not overly revealing, error responses. It’s important to differentiate between client errors and server errors and ensure that error responses do not disclose sensitive data.

7. API Versioning and Documentation

Maintaining API versioning and clear documentation is not directly related to security, but it is essential for secure API development. Versioning ensures backward compatibility and allows developers to introduce changes or security enhancements without disrupting existing API consumers. Additionally, comprehensive and up-to-date API documentation helps developers and clients understand the API’s functionality, security requirements, and best practices for integration.

8. Secure Transport Layer

All API communication should be encrypted using secure protocols such as HTTPS. Ruby on Rails provides built-in support for configuring and enforcing HTTPS connections. Developers should obtain and install valid SSL/TLS certificates and ensure that API clients are configured to communicate over secure channels.

9. Logging and Monitoring

Logging and monitoring play a vital role in detecting and responding to security incidents. Developers should implement comprehensive logging mechanisms to record API requests, responses, and errors. Additionally, integrating with logging and monitoring solutions allows for real-time monitoring and alerts in case of unusual or suspicious API activity.

Ruby on Rails Security Best Practices: Deployment and Maintenance 

Deploying and maintaining a Ruby on Rails application securely is not just a matter of preference; it is an absolute necessity in today’s digital landscape. With cyber threats constantly evolving and becoming more sophisticated, businesses face significant risks if they neglect to prioritize robust security measures throughout the application’s lifecycle. 

Moreover, a comprehensive security strategy involves more than just the initial deployment of an application. It requires ongoing vigilance and continuous monitoring to detect and respond to security incidents promptly. By implementing continuous monitoring and auditing practices, businesses can proactively identify and address potential security breaches and minimize the impact on their systems and their customers.

We have prepared for you a Checklist of 8 Ruby on Rails Security Best Practices: Deployment and Maintenance that will help your developers to keep track of what needs to be done to ensure the security of your RoR application. You can download it for free from the link below.

8 Ruby on Rails Security Best Practices: Deployment and Maintenance

Ensuring Ruby on Rails Security with MobiDev

Ruby on Rails, with its robust framework and security-focused features, provides developers with the necessary tools and resources to build highly secure web applications. By implementing secure coding practices, leveraging security-focused gems, securing APIs, and following best approaches for deployment and maintenance, businesses can enhance the security posture of their Ruby on Rails apps and protect their valuable data. 

But only an experienced development team can discover and apply all the security features of Ruby on Rails in terms of the specific tasks of a particular project. Ruby on Rails developers at MobiDev have years of experience in developing RoR web applications and upgrading existing Ruby products. Our engineers are skilled enough to prioritize security without compromising functionality and user experience of web projects. 

If security plays a key role in your product and you want to bring in experts in this field to get the job done in the most efficient way, don’t hesitate to contact us to find out how we can meet your needs.

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