Jämförelse av statiska kodanalysverktyg : En fallstudie om statiska kodanalysverktygs förmåga att hitta sårbarheter i kod

Sammanfattning: Security deficiencies that occur in web applications can have major consequences. PHP is a language that is often used for web applications and it places high demands on how the language is used to ensure it is safe. There are several features in PHP that should be handled with care to avoid security flaws. Static code analysis can help find vulnerabilities in code, but there are some drawbacks that can occur with static code analysis tools. One disadvantage is false positives which means that the tool reports vulnerabilities that do not exist. There are also false negatives which means the tool cannot find the vulnerability at all which can lead to a false sense of security for the user of the tool. With the help of completed test cases, three tools have been investigated in a case study to find out if the tools differ in their ability to avoid false positives and false negatives. The study also examines whether the tools' rules consider the PHP language's vulnerable functions. To answer the research question, a document collection was conducted to obtain information about the tools and various vulnerabilities. The purpose of this study is to compare the ability of static code analysis tools to find PHP code vulnerabilities. The tools that were investigated were SonarQube, Visual Code Grepper (VCG) and Exakat. The study's analysis shows that VCG found the most vulnerabilities but failed to avoid false positive vulnerabilities. Exakat had zero false positives but could not avoid false negatives to the same extent as VCG. SonarQube avoided all false positives but did not find any of the vulnerabilities tested in the test cases. According to the rules of the tools, VCG had more consideration for the risky functions found in PHP. The study's results show that the tools' ability to avoid false positives and false negatives differed and their adaptation to the PHP language's vulnerable functions.