Table of contents

• Common coding vulnerabilities
• Secure coding guidelines and best practices
• Tools and automation in secure software development
• Conclusion

Secure coding refers to designing and writing software with security in mind from the outset. It is a core aspect of secure software development, ensuring applications are resilient against attacks by eliminating vulnerabilities in code. By following rigorous secure coding practices (also known as secure coding guidelines), developers can prevent issues like SQL injection, buffer overflows, and cross-site scripting before they ever reach production. This proactive approach, often called "shifting security left," means addressing security during development rather than after deployment, greatly reducing the risk of breaches.

Attackers frequently exploit common weaknesses such as improper input validation, broken authentication, and insecure access controls. In the sections below, we explore how to avoid common coding vulnerabilities by adhering to proven secure coding guidelines and using the right tools. We will define key vulnerability types, highlight best practices, and show how modern tooling (including Graphite's code review features) helps in preventing security vulnerabilities in code.

Common coding vulnerabilities

• Injection flaws: Occur when untrusted input is interpreted as code or commands. For example, using un-sanitized user input in a SQL query could allow an attacker to inject malicious database commands. In web contexts, this includes cross-site scripting (XSS) attacks where a malicious script is injected into pages and executed in users' browsers.
• Broken authentication & access control: Weak authentication or missing authorization checks allow attackers to gain unauthorized access. For instance, poor session handling or predictable user identifiers can enable account hijacking or unauthorized data access.
• Security misconfiguration & sensitive data exposure: Using insecure default settings (e.g., default passwords) or failing to encrypt sensitive data can leave an application exposed. Mistakes like hardcoding credentials or using outdated cryptography make it easy for attackers to steal data.
• Vulnerable dependencies: Outdated third-party libraries and frameworks may contain known vulnerabilities. If your code relies on such components, attackers can exploit those flaws – so keep libraries up to date and apply patches promptly.

Secure coding guidelines and best practices

By following fundamental secure coding guidelines, developers can significantly reduce the risk of vulnerabilities. Key best practices include:

• Validate and sanitize inputs/outputs: Check all inputs for validity (e.g., correct type and length) and sanitize or encode outputs derived from user data to thwart injection attacks. Use parameterized queries for database operations instead of string concatenation to avoid SQL injection.
• Enforce least privilege: Each user or component should have only the minimum access rights necessary (principle of least privilege). All sensitive functions and data must require proper authentication and authorization, reducing the chance of privilege abuse.
• Protect sensitive data: Always apply strong encryption for data in transit and at rest. Never store passwords or secrets in plain text, and disable or change default credentials. Configuring applications securely (using secure defaults and turning off unused features) further reduces the risk of exposing data.
• Keep dependencies updated: Regularly update third-party libraries and frameworks to patch known issues. Monitor for new vulnerabilities in your dependencies and promptly apply security patches.
• Handle errors and logging safely: Show generic error messages to users while logging full error details internally for developers. Avoid logging sensitive information that could be abused if seen by unauthorized parties.

Additionally, perform regular security testing and code reviews to catch issues early. Techniques such as penetration testing, automated scanning, and peer reviews with a security checklist help ensure the above practices are consistently followed.

Tools and automation in secure software development

Development teams leverage automation to enforce security. Static analysis tools (SAST) and dependency scanners can detect many flaws and known vulnerabilities in code before it's merged. Integrating these checks into the CI/CD pipeline ensures each code change is automatically scanned for issues.

However, human code reviews remain crucial to find logic issues that automated scans might miss. Involve experienced developers or security experts to review critical changes – they can often spot subtle vulnerabilities through manual inspection. Automated assistance can augment this process, from linters that comment on insecure code patterns to AI-based reviewer tools.

Graphite for secure code reviews

Graphite provides tools to enhance security during code review. Its Protections feature lets teams enforce custom security rules on pull requests (e.g., requiring security-team approval for changes to sensitive code and mandating a static analysis scan to pass before merge).

Graphite's AI-powered code reviewer, Diamond, further helps by automatically flagging potential security vulnerabilities in code changes and even suggesting fixes that developers can apply with one click.

Conclusion

Secure coding is an ongoing commitment, not a one-time task. By proactively applying secure coding guidelines and using the right tools (such as Graphite for intelligent code review), development teams can prevent common vulnerabilities and significantly improve their code's security posture. Baking security into every step of development – and double-checking via reviews and testing – ultimately pays off with fewer breaches and greater confidence in the code.