The more critical an application is to the functioning of a company, the more the quality of its code has an impact. When an application malfunctions, it impacts both the productivity of the company and the brand image. This is especially true when the application is a management or business application because they have additional requirements:
- Users need the app to be higher functioning
- They need to be increasingly efficient yet increasingly complex technology (more so since the introduction of cloud application services)
- The app needs to be accessible on multiple platforms and languages
- You need to establish distributed teams
The most important thing, though, is that the application needs to be secure. To be security compliant, it is necessary to ensure that each phase of the application building process focuses on security, from construction to implementation. However, a large number of vulnerabilities are only discovered after the software is released. And most vulnerabilities result from negligence or carelessness in the development stage. To prevent this from happening, you need a source code audit.
What is a Source Code Audit?
A source code audit is a process of analyzing the source code of an application with the objective of discovering security vulnerabilities, security design problems, and places of potential improvement in programming practices. After the analysis, a report is generated that is used to implement a range of measures that guarantee the security and reliability of the code.
Code audits can be carried out in parallel with penetration tests. They can test the exploitability of code vulnerabilities to better estimate the risk they pose. Ideally, code audits are performed throughout the application lifecycle. The faster a vulnerability is discovered, the easier it is to fix!
Audit Objectives and Benefits
Creating secure applications assumes security compliance at all stages of development. It is necessary to develop a security architecture that sees the implementation of code that is free from typical programming flaws as the target goal. In some cases, in addition to implementing secure design and coding, it is necessary to evaluate the environment in which the application will be inserted. This evaluation will aim to protect the software from atypical or adverse situations and provide seamless functioning.
Code audits allow you to identify vulnerabilities in software applications and their causes. Code auditing identifies if:
- Development practices respect secure programming precepts;
- Controls are effective in mitigating risks;
- Vulnerable code practices are being followed;
- There are configuration problems (due to ignorance of the system);
- The system is poorly designed (non-functional requirement); and
- There are coding errors (due to lack of knowledge or inattention).
Additionally, source code auditing can provide answers to other critical questions:
- Is the application maintainable?
- Could performance be a problem?
- Can the scalability of the application be done simply?
- What about version upgrades?
- Is the documentation sufficient?
How to Ensure Compliance
Auditing is a very effective technique for identifying security flaws, as more than half of the vulnerabilities are caused by implementation failures. Thus, companies are increasingly looking for detailed feedback on how they can improve their software development lifecycle, save time and money, and bring more security to users.
Code auditing can be performed in three ways: static, dynamic, or manual. See below the pros and cons of each model:
This is the oldest method for source code auditing: detecting vulnerabilities and programming problems. However, to perform manual analysis, the professional needs to have a good understanding of the architecture, and the code must be accompanied by comments and a summary of the functionality of each method.
This means that this analysis model can be slow to detect anomalies in the source code and become tiresome. As part of this analysis model, some companies adopt “peer reviewing”—a new piece of code can only be accepted into the main codebase if it is reviewed by another developer. In this case, as the analysis is incremental, the slowness and overhead are less.
In this model, verification of the source code is automatic and usually takes place at compilation. A widely used tool for this is FindBugs. It inspects Java bytecode in search of bug patterns without executing the program code.
Through a set of techniques such as flow control and pattern searching, static analysis identifies simple and complex failures. However, they only report the vulnerabilities for which they were programmed. The consequence of this is that vulnerabilities not covered by the tool can be missed.
Static analysis uses the following features:
- Analysis of the entire source code
- Tracking points of interaction with other processes or users
- Search for role subscriptions
This audit model analyzes the behavior of the running application. It plays the role of a hacker trying to find a vulnerability while the application is running. The great advantage of this type of analysis is the possibility of unearthing other vulnerabilities that cannot be found by just studying the code, such as a configuration error on the web server, for example.
Often, static and dynamic testing are seen as opposites, which is not true. When you weigh the advantages and disadvantages of each, you quickly realize that both can yield interesting benefits and insights.
It is important to have the most complete and objective view of things possible. A source code audit is a real inventory of the code elements. Once the source code audit has been carried out, it is essential to work on a matrix of valued actions. This projection provides decision-makers with clear visual elements to use to strategize the future of the application and its source code.
Performing an audit is a great way to assess the quality of your application. There are many code auditing practices you can adopt. It is often beneficial to implement a preventive code quality approach, which performs lighter but more regular audits. Auditing an application before putting it into production also seems to be a significant plus. The options are endless.