Security is most effective when it’s built into the app from day one, not added as a patch to address a specific problem. Fixing vulnerabilities is also more costly if you do it late in development or even after development.
In this article, we’ll go over a checklist of steps a developer can take to set up security so their web app addresses breaches before they happen. The checklist isn’t comprehensive. Instead, it should be seen as a baseline that every app should cover.
Define Security Requirements Early
Before writing any code, the developer team should define security expectations. They depend on the type of app you’re building and the users you’re targeting.
The checklist:
· Identify the type of data the app will collect, store, and process.
· Classify the data that may be sensitive (payment data, personal information, credentials).
· Define the authentication and authorization needs. Experts such as those from CryptoManiaks have written about regulations that guide which of these needs are essential and regulated by law. For instance, knowing your customers’ laws is becoming a necessity for crypto payments.
· Create a basic threat model.
· Agree on the acceptable level of risk for the user, because there will always be some risk.
The goal of such an approach is to build the app from the ground up by anticipating users’ needs and, therefore, the outcomes of the security measures.
Secure Design and Architecture
Strong security design and architecture are more important than a good code fix.
The checklist:
· Use well-maintained frameworks with active security updates.
· Apply the principle of least privilege to users, services, and APIs
· Make sure to separate the frontend, backend, and database layers.
· Define the trust boundaries between inside and outside components. · Limit public-facing endpoints to use only when necessary.
A secure architecture limits the points at which the app can be attacked by outsiders. By making the surface as small as possible, the developers reduce the chance of an attack in the first place.
Input Validation and Output Encoding
Untrusted input is one of the most common sources of web security vulnerabilities.
The checklist:
· All inputs should be treated as untrustworthy by default, and the users should prove that they are not a threat.
· Strict server-side input validation is a must.
· It’s better to have allow-lists than blocklists.
· Encode output based on context (HTML, JavaScript, CSS).
· Validation should be centralized.
The goal of such an approach is to prevent unstructured data from altering the web app’s behavior. It stops common attacks and prevents them from reaching databases or core logic.
Data Protection and Secure Transport
Data should be protected both when it’s stored and when it’s moved.
The checklist:
· HTTPS/TLS should be enforced throughout the application.
· Sensitive data should be encrypted when it’s at rest.
· Encryption keys need to be stored securely and rotated regularly.
· Sensitive pages shouldn’t use caching even though it’s less user-friendly.
· Logs and responses should minimize data exposure.
Sensitive data is part of the web app and should be stored and protected with the utmost care. The goal of these measures is to protect users at their most vulnerable stage.
Secure Configuration and Deployment
Misconfigured systems are vulnerable points that attackers could use.
The checklist:
· Use secure default settings for servers and frameworks.
· Features that aren’t used and upgraded should be removed. The same goes for test endpoints and demo codes.
· Separate development, staging, and production environments.
· Default accounts and credentials pose a threat; it’s best to disable them. · Regularly patch servers.
Human error, outdated software, and misconfigurations cause security risks. A hardened deployment environment has fewer entry points for attackers.
Logging, Monitoring, and Error Handling
Deployment is not the end of security; it’s also important for developers to have visibility.
The checklist:
· Log authentication attempts and access control failures.
· Sensitive data used during log-ins shouldn’t be logged.
· Users should get only a generic error message.
· Logs for analysis and alerting should be centralized.
· Unusual and risky behavior should be logged and stored.
The objective is to maintain a log of security issues without exposing any security information in the process. With good visibility, the team can respond to threats right away.
Testing and Continuous Improvement
Security must evolve so that it responds to new threats and issues
The checklist:
· Run static code analysis during development.
· Dependencies should be scanned for vulnerabilities regularly.
· Re-test after each major update or infrastructure change.
· Perform a penetration test before releasing a web app to the public.
· After a security incident, update the security practices.
The end goal of these points is to catch vulnerabilities when they appear and adapt and change the code accordingly. Continuous testing is the only way to stay on top of new threats.
