Common Web Application Security Mistakes in Companies

Web applications are the backbone of modern businesses, from e-commerce platforms to internal management tools. Despite their importance, companies often make critical security mistakes that put data, finances, and reputation at risk. Understanding these mistakes through real-life examples helps both technical staff and non-technical stakeholders grasp the risks.

1. Ignoring OWASP Top 10 Vulnerabilities

Many companies overlook the most common web vulnerabilities listed in the OWASP Top 10. For instance, SQL Injection has been exploited in high-profile cases like the 2019 Capital One breach, where a misconfigured web application firewall allowed attackers to access over 100 million customer records. Similarly, XSS attacks can occur when user input is not properly sanitized. A simple example is a comment box on a website that allows attackers to inject JavaScript code, which can steal session cookies from other users. Non-technical staff should understand that even “small” input fields can become attack points if ignored.

2. Weak Authentic0ation and Authorization

Weak or default passwords, lack of multi-factor authentication (MFA), and poor session management remain prevalent. In the 2021 LinkedIn data leak, attackers exploited weak password recovery mechanisms to access sensitive account information. Another example is an internal dashboard that uses the same password for all employees; if one password is leaked, the entire system is compromised. Teaching employees the importance of MFA and password hygiene can prevent such breaches.

3. Insecure Data Handling

Companies often store sensitive data without proper encryption or inadvertently expose it. For example, in the 2018 Facebook-Cambridge Analytica scandal, personal user data was collected without consent due to insufficient data protection. Another common mistake is leaving API keys or passwords in public GitHub repositories. Even if a system uses encryption, transmitting sensitive data over HTTP instead of HTTPS can allow attackers to intercept it. Non-technical employees should understand that handling personal or financial data carelessly can have serious legal and reputational consequences.

4. Failure to Patch and Update

Outdated software and libraries are a major source of vulnerabilities. The Equifax breach in 2017 occurred because the company failed to patch a known Apache Struts vulnerability, exposing the sensitive financial information of 147 million people. Regular patch management and updates are crucial to prevent attackers from exploiting known vulnerabilities. Technical staff should maintain a patch schedule, while management should ensure operational support for updates.

5. Poor Input Validation

Allowing unchecked user input is a common gateway for attacks. For example, a web form that allows users to submit data without validation can be exploited to execute SQL Injection or XSS attacks. A practical example: a search box that fails to filter input can allow an attacker to insert malicious scripts that redirect users or steal their cookies. Non-technical staff should recognize that even simple features, like a feedback form, need attention for security.

6. Lack of Security Testing

Some organizations rely solely on developers to secure applications or assume functional testing is enough. Without regular vulnerability scans, penetration tests, or bug bounty programs, many vulnerabilities go unnoticed. For example, a startup that skipped security testing ended up exposing user accounts via a predictable password reset function. Management must understand that investing in security testing is not optional, it’s essential.

7. Misconfigured Security Settings

Leaving development settings or debug modes active in production, weak SSL/TLS configurations, and improper file permissions are common mistakes. For example, attackers have exploited debug pages left on production websites to gain administrative access. Even small misconfigurations can open doors for attackers. Training staff to check configurations and restrict access can mitigate these risks.

8. Lack of Security Awareness

Employees are often the weakest link. Phishing, accidental disclosure of credentials, or embedding sensitive keys in code can compromise systems. For instance, several corporate breaches started with a simple phishing email that tricked an employee into revealing their password. Non-technical staff need basic awareness training to recognize phishing attempts, use secure passwords, and handle sensitive data responsibly.

Conclusion

Web application security is not just a technical problem; it is a shared responsibility across the organization. Companies must combine secure coding practices, regular testing, timely patching, and employee awareness programs. By learning from past breaches and understanding common mistakes, both technical and non-technical staff can help protect critical data, maintain customer trust, and avoid costly security incidents.