Best Practices for the Perfect Secure Code Review
Best Practices for the Perfect Secure Code Review
When you think you have secured your software by introducing some security patches, adding a security test to your development process and your work is done, you are wrong! Your code is what stands between a hacker and data of your customer, product, and intellectual property. And if you skip the most crucial step of secure code review, then you are putting it at risk.
Secure code review is a practice used as a part of the compliance requirements. Similar to code review, the primary focus of this process is to create an extra layer of security vulnerability check to your development process before rolling out your product. In this, the organization goes through multiple checks manually by a reviewer or automated by a tool. If you are unfamiliar with code review, you can find more about it from another blog, “Why is code review important?”
Secure code review is an important process, mandatory for any software being developed for healthcare, banking, military, or any sector where security is the first priority. Application-level security is increasingly coming under fire.
With many hackers lurking in search of security vulnerabilities in code and cracking them, secure code review becomes a need for any software irrespective of sector. So we look at the best practices to do a perfect secure code review.
Creating a code review checklist
Code review is a complex process with multiple checks, some of it you may forget. Every software has its security requirements, and hence, the tests would differ as well. To make sure you don’t miss any of these checks, build a code review checklist before you undertake the process.
The list must be comprehensive and have all the expectations, results, and standards noted that were set for the project. It must contain parameters that are measurable and applicable to your code. While developing, consider factors like risk, lines of code, programming language, purpose & context, resources, time, and deadlines. You can get an overview of how a code review checklist should look like from our blog – “The Ultimate Code Review Checklist”
From regularly, we don’t mean time to time, but whenever a significant change is brought into your software. You don’t need to wait for the development process to complete for code review to take place. This is where a secure code review differs from a general review. Any change that is made or any addition that is done in your software may create a loophole or similar open end for hackers to exploit.
Reviewing regularly with tests will result in more secure and higher quality code, making future implementations easy, less expensive, and quick. Try using an automated code review tool that can do this in a matter of seconds for you like CodeGrip.
Validate your Input and Output
The major part of actually performing a security code review is analyzing the attack surface. The software takes input to produce some output. Therefore the first aim is to identify all types of inputs. Most of the security vulnerabilities are found at the input itself. Review input from all external data sources and validate the output from untrusted objects as input as well.
Validate inputs from the browser, cookies, property files, external processes, data feeds, service responses, flat files, command line, and environment variables. Input and output define the trusted boundary of a system, with a secure input lookout for security vulnerabilities at your output that can result in data-stealing or loss. Keep an eye open for any way that an unwanted external source can attach itself with your output.
Principle of Least Privilege
The principle of least privilege (POLP) or sometimes also known as the principle of least authority is the idea that any program, process, or user should have the minimum privilege necessary to operate. These minimum privileges are the exact necessity to complete the job. For example, a user account responsible for creating legacy codes does not need access to your financial records.
If at any time of period a user needs admin rights, it must be provided for only the minimum time required to complete that process. Using PLOP minimizes the attack surface for hackers to act on making your code secure.
A term made famous by Microsoft in their book Secure Development Lifecycle is a structured representation of all the information that affects the security of software or may do so in the future. It is done to improve decision making during secure code review.
Threats are rated according to the severity or complexity and arranged. Here risks can be some leaky codes, events like DoS attack or incidents like storage failure. Ideally, a high-level threat model should be prepared at an early stage of code and then refined throughout the lifecycle. Threat modeling provides a clear path to securing code.
Creating Notes for Future
Secure code review is a learning process. Every time you review your or other developer’s code, you discover many insights. Apart from learning new techniques or finding new issues, you also learn how your peer developer approaches to coding. Creating notes of the process may prove to be beneficial in future reviews as well as for your colleagues to get a better chance of learning new things. A positive security culture prompts better development, facilitating your team’s awareness in a positive manner.
You can follow all of this or use CodeGrip!
Manual secure code review is a lengthy procedure that requires security experts as reviewers. It is hard to follow and even more challenging to perform. It calls for a need for a tool that can perform an automated code review on any code or language.
CodeGrip is a free-to-try tool that analyses your software’s source code using all security checks to find out vulnerabilities that it may have. It arranges these security vulnerabilities according to the severity and location. It also provides a suggested solution to the problem making sure that your software is impenetrable. CodeGrip makes secure code review an easy task that you can repeatedly perform without thinking about the cost, time, and effort.