Node.js is an open source development platform for running JavaScript code on the server side. Node is useful for developing applications that require a persistent browser-server connection and is often used for real-time applications such as chat, social applications, or news feeds.
DevSecOps is a way for development, security, and operations teams to work together throughout the project life cycle. It is often implemented by adding security to existing DevOps teams and agile processes.
The idea behind this collaboration is to incorporate security early in the development process. This is called shifting security left. As security moves to the “left” of the development process, application vulnerabilities and bugs are discovered and addressed faster. This leads to more secure product releases with a reduced need to apply patches and troubleshoot in production. Applying DevSecOps to Node.js development can improve both the efficiency and security of Node.js projects.
Common Node.js Attack Vectors
Here are a few cyber threats that affect many Node.js applications.
Cross-Site Scripting (XSS)
XSS attacks inject manipulated client-side JavaScript code. Web apps are vulnerable to XSS if they don’t validate inputted hostnames from the DNS. Attackers can use forms to enter malicious scripts and hack into the system. In some cases, entering code into the filename can trigger cross-site scripting in the target browser.
A hacker can use your file upload form to hack into your system. There are many ways for this vulnerability to lead to a system compromise. Though usually mitigated by modern front-end frameworks, in some cases it may happen that putting javascript into the filename will trigger XSS in a user’s browser, allowing the theft of session IDs. In other cases, an attacker might get sensitive server information by uploading a file to the Node.js server and running it by exploiting a path traversal vulnerability.
Code Injection
Developers are responsible for writing secure application code, but it’s impossible to fully guarantee the code’s security when using open source components. A code injection attack involves injecting malicious code into the target system and forcing the application to execute it, allowing attackers to access the codebase. Inadequate data validation often results in code injection vulnerabilities.
Default Cookie Names
Cookies help web apps identify specific users by storing user actions in the underlying infrastructure (e.g., an eCommerce shopping cart that remembers the items a customer selects).
Developers should use custom names for cookies (rather than defaults) to prevent attackers from identifying and targeting cookies and extracting data.
Brute Force Attacks
Brute force attacks often affect Node.js applications. An attacker randomly generates millions of passwords to find one that works, logging in to the application. You can prevent brute force attacks by strengthening the authentication mechanisms, limiting the number of permitted login attempts from a single IP, and encrypting stored passwords (using bcrypt.js).
Cross-Site Resource Forgery (CSRF)
This type of session hijacking forces an authenticated user to execute malicious actions on the target web application. The attacker hijacks a legitimate user’s session to bypass security controls and change the application’s state. CSRF can force users to transfer funds or change their account details, potentially compromising the web application’s security.
Node.js Security Best Practices
Implement Strong Authentication
A compromised, weak, or incomplete authentication mechanism is a common vulnerability. Many developers think of authentication as something that “just works”. However, authentication can easily be bypassed by attackers if not implemented correctly.
In Node.js, you have the option of using the default Node.js authentication solution. There are a few things to keep in mind:
- Do not use Node.js’s built-in password library when generating passwords, use Bcrypt.
- Limit failed login attempts and do not notify users if their username or password is incorrect. Instead, return a generic “Invalid Credentials” error.
- Have a robust session management strategy.
- Implement two factor authentication (2FA). This can be done using modules like node-2fa.
Alternatively, use one of many third-party solutions available for application authentication, which may be superior to built-in Node.js functionality.
Avoid Errors That Reveal Too Much
There are many things to consider when building error handling functionality:
- Don’t give the user any details they don’t really need. Never return the entire error object to the client. It may contain information that you do not want to disclose, such as paths, other libraries you are using, or secrets.
- Wrap the path in a catch clause so that Node.js doesn’t crash if the request triggers an error. This prevents the app from crashing continuously, allowing attackers to send malicious requests that cause the app to crash.
- Don’t expose your Node.js app directly to the internet. Use a component like a load balancer, cloud firewall or gateway. This means DoS attacks will be one step removed from your Node.js application.
Using Security Linters to Capture Vulnerabilities in Code
Code linters help identify various issues in code before compiling. They let you detect the most common issues and ensure you follow best practices.
Code linters have their own rules, which you can customize according to your requirements. Before using a linter, make sure you enable rules related to security vulnerability detection in the linter configuration.
Server-side Logging and Monitoring
A good logging library provides developers with powerful troubleshooting and monitoring capabilities. On the other hand, unnecessary or excessive logging affects application performance and consumes more resources. Therefore, you should only use reasonable log levels when deploying applications to production environments.
When constructing log messages, they must be in a format that can be read and understood by humans and machines. Logging ambiguous messages can lead to misunderstandings among developers. An error message must not only describe the problem but also advise what the user can or should do to fix it.
It is also important to ensure that your logging mechanism captures all relevant information such as IP addresses, usernames, and actions taken.
Never retrieve or store sensitive information in application logs. This violates compliance standards such as PCI and GDPR. However, there are times when you need to record this information for troubleshooting – in this case, it is recommended to mask or anonymize sensitive information before writing it to the log.
Implementing Node.js Security in a DevSecOps Organization
Node.js security best practices are well known and security awareness is growing among Node.js developers. However, many organizations don’t have a clear organizational structure for implementing development best practices. Here are a few steps your organization can take to transition a Node.js development team to a full DevOps model:
- Adding mandatory guard rails for developers
For example, adding static application security testing (SAST) within the IDE and on every commit. Linters should be deployed centrally with a consistent configuration for all developers in the team.
- Automated security testing in staging environments
During the CI/CD process, when a Node.js application is deployed to a staging environment, there should be automated tests that can identify security misconfigurations and integration-related vulnerabilities. Dynamic application security testing (DAST) tools are ideal for this purpose.
- Runtime protection
No DevSecOps process is complete without a safety net to identify security issues in production. This requires the use of tools like web application firewalls (WAFs), which can detect and block malicious traffic, and runtime application self-protection (RASP), which can proactively respond to attacks. Both these tools provide feedback to DevOps teams to help them identify and remediate vulnerabilities in the underlying application.
By implementing these three stages, you can be sure that Node.js security is not just an ad-hoc practice but a formalized, coordinated process involving developers, operations teams and security experts.
Conclusion
In this article, I explained the basics of DevSecOps and how to secure Node.js:
- Implement strong authentication—In Node.js, you have the option of using the default Node.js authentication solution.
- Avoid errors that reveal too much—Don’t give users more details than they actually need when displaying errors.
- Using security linters to capture vulnerabilities in code—Code linters help identify various issues in code before compiling.
- Server-side logging and monitoring—A good logging library provides developers with powerful troubleshooting and monitoring capabilities.
I hope this will be useful as you implement Node.js security in your DevSecOps organization.
