Code review is a primary element of application and software hardening. Code review is a process of examining the source code of an application or software to identify and fix errors, vulnerabilities, or inefficiencies that may compromise its functionality, security, or performance. Code review can help prevent common security risks such as buffer overflows, SQL injections, cross-site scripting, or logic flaws. Code review can also help improve the quality, readability, maintainability, and usability of the code. Code review can be done manually by developers or peers, or automatically by tools such as static code analyzers or code quality checkers.

Vulnerability analysis, database configuration, and software repository are also important for application and software hardening, but they are not primary elements. Vulnerability analysis is a process of identifying and assessing the weaknesses or flaws in an application or software that may expose it to attacks or exploitation. Vulnerability analysis can be done by tools such as vulnerability scanners or penetration testers. Database configuration is a process of setting up and managing the parameters, options, or features of a database system that stores or processes data for an application or software. Database configuration can include aspects such as access control, encryption, backup, recovery, performance tuning, or replication. Software repository is a location where the source code, binaries, or documentation of an application or software are stored and managed. Software repository can facilitate version control, collaboration, distribution, or deployment of the application or software.