OWASP Top 10 and the Security Vulnerabilities Tested in Web Applications

What Is the OWASP Top 10?

OWASP (Open Worldwide Application Security Project) is a globally recognised, independent security community that identifies the most common and most critical security risks in web applications. The OWASP Top 10 list is compiled by analysing millions of real security vulnerabilities and is regarded as one of the most important references for assessing the security level of web applications. Web application penetration tests carried out by SecureSys are performed in line with the OWASP Web Security Testing Guide (WSTG) and OWASP Top 10 methodologies.

OWASP Top 10 (2021) Categories

Security Risk	Description	Business Impact
Broken Access Control	Bypassing authorization controls	Unauthorised access to critical data
Cryptographic Failures	Faulty encryption or data protection	Disclosure of sensitive data
Injection	SQL, NoSQL, LDAP and similar injection attacks	Database breach and data loss
Insecure Design	Lack of security-focused design	Business logic vulnerabilities
Security Misconfiguration	Incorrect system or server configuration	Unauthorised access and system compromise
Vulnerable & Outdated Components	Out-of-date software components	Exploitation of known vulnerabilities
Identification & Authentication Failures	Authentication weaknesses	Account takeover
Software & Data Integrity Failures	Gaps in code and data integrity	Execution of malicious code
Security Logging & Monitoring Failures	Insufficient logging and monitoring	Attacks going unnoticed
Server-Side Request Forgery (SSRF)	The server making requests on the attacker's behalf	Access to internal network resources

Key Security Controls Evaluated in SecureSys Tests

Because of their frequency and impact, some OWASP Top 10 categories are covered by dedicated, in-depth pages at SecureSys:

• SQL Injection — the most critical sub-topic of the Injection category.
• Cross-Site Scripting (XSS) — Stored, Reflected and DOM-Based types.
• Broken Access Control — IDOR, BOLA, horizontal/vertical privilege escalation.
• Identification & Authentication Failures — MFA, brute force, session management.
• API Security — the scope of the OWASP API Security Top 10.
• Business Logic — the practical extension of the Insecure Design category.

Other Critical Areas Also Tested

Cryptographic Failures

TLS configurations, SSL certificates, encryption algorithms, hash algorithms, password storage methods and key management are tested to assess whether user information is protected securely.

Security Misconfiguration

Configuration-related risks such as debug modes left on, default user accounts, incorrect CORS settings, directory listing and out-of-date software versions are checked.

Cross-Site Request Forgery (CSRF)

Whether operations such as changing a password, transferring money or granting privileges can be performed without the user's knowledge while their session is open is tested; CSRF token usage and SameSite cookie settings are examined.

Server-Side Request Forgery (SSRF) and XML External Entity (XXE)

SSRF vulnerabilities can allow the server to reach systems on the internal network, while XXE can allow access to server files through misconfigured XML parsers. Both scenarios are tested with techniques targeting classic and cloud environments.

Insecure File Upload

File extension filters, MIME-type validation, magic-byte checks and web-shell upload attempts are evaluated.

Secure Session Management

Secure cookie, HttpOnly, SameSite, session timeout, session fixation and session hijacking scenarios are analysed.

Why Is the OWASP Top 10 Alone Not Enough?

One of the common mistakes organisations make is to assess security only against the items on the OWASP Top 10 list. Yet today a significant proportion of successful attacks stem not from direct technical vulnerabilities but from logical gaps in the application's workflow. For example, in a finance application a user may appear to be able to view only their own accounts, but if another customer's data can be reached by changing a parameter in the request, this is a classic business logic and authorization problem. Such vulnerabilities often cannot be detected by automated scanners; experienced experts must perform manual analysis and develop attack scenarios.

At SecureSys, we use automated tools and manual analysis together in our tests, give special attention to business logic and authorization controls, and report risks not only by detecting them but also with actionable remediation recommendations.

To have your web application tested against the OWASP Top 10 and beyond, reach out via our Web Application Penetration Testing Service page.