Secure coding practices every developer should know
In today’s interconnected, software-dependent world, releasing secure apps has become a top priority for developers. The good news is that many potential exploits and attacks can be prevented through writing better and more secure source code.
Source code is a set of instructions that defines an application’s behavior and implements its functionality. It is essentially the DNA of an application. Source code is translated into instructions, which are then read and performed by a computer.
What Is Secure Coding?
Secure coding, also referred to as secure programming, involves writing code in a high-level language that follows strict principles, with the goal of preventing potential vulnerabilities (which could expose data or cause harm within a targeted system). Secure coding is more than just writing, compiling, and releasing code into applications. To fully embrace secure programming, you also need to create a secure development environment built on a reliable and secure IT infrastructure using secure hardware, software, and services and providers.
Why Is Secure Coding Important?
More and more financial transactions are also moving online. Security incidents often originate deep in an application’s underlying software and can have serious consequences for businesses and individuals alike. Insecure code in important industries (e.g., finance, healthcare, energy, and transport) could result in financial and property damages, market manipulation and theft, even physical harm and fatalities.
And the danger is real: Media reports in recent years have highlighted just how insecure much of the software we use is. Even major organizations with the resources and knowledge at their disposal have experienced serious data breaches. For companies that provide software to consumers or enterprises, customer trust is of course extremely valuable, and losing that trust could impact their bottom line. Ensuring secure coding practices therefore must be a top priority for these organizations.
Getting Started with Secure Coding
When it comes to secure programming practices and security in general, keeping the entire process as simple as possible (KISS) is the way to go. Complex procedures can lead to inconsistent results or worse, they may be ignored completely. You should avoid reinventing the wheel and stick to proven security and secure coding best practices. The OWASP Foundation offers many valuable resources, among them the OWASP Top 10, which features the most common security risks and is thus a good starting point.
Access control, which includes authentication and authorization, is one of the basic building blocks of protecting your system.
Enforcing strong encryption is another important aspect of keeping your system secure. There are many readily available libraries to help you implement encryption, thus requiring minimal custom code be written. It’s, however, important to only use standard algorithms and libraries. You should also ensure that whenever FIPS compliance is required only validated libraries are used.
Secrets management is another important security measure. Whether or not you choose to use one of the many available tools to help you manage secrets, you should never hardcode or upload secrets such as passwords or access keys to code repositories.
The above measures will protect your system and are thus the first line of defense, but it’s also critical to make your code itself more secure.
5 measures to include in your secure coding practices checklist:
- Avoiding shortcuts: It can be tempting for developers to want to take shortcuts to release code into production faster, but this could have serious security implications. For example, attacks often occur when hardcoded credentials and security tokens are left as comments. This information should be cleaned up long before your apps are released. But as your code base gets bigger and there is mounting pressure to deliver working code on increasingly tight release schedules, the likelihood of security gaps goes up.
- Automated scanning & code reviews: Cross-site scripting (XSS), SQL injection, and other types of attacks can exploit security vulnerabilities in your code. Both XSS and SQL injection attacks result from weakness in your code that fails to distinguish between data and commands. XSS executes malicious code under your domain. SQL injection attacks attempt to steal or manipulate data in your internal data stores. A combination of regular secure code reviews and automated tools that scan your code for these vulnerabilities can help prevent such attacks.
- Avoiding components with known vulnerabilities: While open-source components and libraries, often consumed as packages, can save developers time and energy, they are also a common entry point for malicious actors and a great source of vulnerabilities and potential exploits. Refraining from using those components with known vulnerabilities and constantly monitoring for new vulnerabilities throughout the development process in the components you use will help you maintain the integrity of your code.
- Auditing & logging: Software with sufficient logging and monitoring will allow you to detect potential incidents when your code is deployed in a production environment.
Snyk is one of the best free tools to scan and monitor your code security. You can use open source vulnerability scanner or Snyk code to find and fix code vulnerabilities with a developer-friendly experience.
The Bigger Picture
Once you’ve got the basics covered, you can take some additional steps to further secure your code. The first step is to adopt a multi-layer security approach. Following best practices and writing secure code are only part of this.
Building a culture of security within your organization is another crucial aspect. This involves educating developers, IT, organizational management, as well as internal and external stakeholders. You should also be actively building threat models and planning to manage potential risks and remediate them. There are a number of available sources to help with this, such as OWASP and Have I Been Pwned.
Building a secure software development life cycle (SSDLC) is another critical step for integrating secure coding practices into your software development process. This involves building and maintaining applications in every stage—from the initial stage of gathering requirements for a new application (or adding features and functionality to an existing app) to development, testing, deployment, and maintenance. At this earliest “gathering” stage, your project stakeholders should already begin reviewing requirements and flagging potential security risks, especially those related to source code.
Using automated tools as part of your SSDLC or other secure coding initiatives can save you time and effort. Static application security testing (SAST) is one example, and it can be implemented very early on in the development cycle.
While conventional Static Application Security Testing (SAST) tools are limited by lengthy scans times and poor accuracy, returning too many false positives, and eroding developer trust. Snyk Code makes developer efforts efficient and actionable. Real-time semantic code analysis provides actionable suggestions right when the code is written bringing speed and quality results into developer workflow.
Tried & True Secure Coding Guidelines
As software has become an integral part of our daily lives, the security and integrity of the underlying source code matters. Many of the secure coding techniques discussed here are not new and are concepts familiar to experienced developers. But keeping it simple and following accepted industry and secure coding standards and procedures will go a long way in reducing your overall attack service—including the number of entry points—and will help you deliver secure software.
Secure Coding FAQ
What are secure coding practices?
Secure coding practices entail writing code in a way that will prevent potential security vulnerabilities. This includes maintaining both your source code and any third-party libraries in a secure state.
What is OWASP secure coding?
OWASP secure coding is a set of secure coding best practices and guidelines put out by the Open Source Foundation for Application Security. It outlines both general software security principles and secure coding requirements.
What is a secure code review?
A secure code review is the process of identifying and remediating potential vulnerabilities in your code. This can be done manually, using automated tools, or a combination.
Continuously scan and test your code for known vulnerabilities with Snyk.