Web applications are often exposed to different types of security risks due to user interactions, data processing, and external connectivity. The OWASP Top 10 provides a widely used reference that highlights the most common vulnerabilities found in web applications. In this blog, we will discuss OWASP Top 10 Vulnerabilities and Prevention Methods.
1. A01:2025 Broken Access Control
Broken access control occurs when an application does not properly restrict what users can view or modify. In many web applications and APIs, attackers attempt to access data or functions by changing request parameters, user IDs, or API endpoints.
This issue often appears when server-side checks are missing, or when applications rely only on user interface restrictions. Attackers may try to access admin functions, view other users’ data, or modify records without proper authorization.
How to prevent it?
To prevent this issue, applications should enforce access checks on the server side for every request. Role-based access control should be implemented and verified for all endpoints. Testing should confirm that users cannot access resources outside their assigned permissions.
2. A02:2025 Security Misconfiguration
Security misconfiguration happens when servers, frameworks, or applications are deployed with insecure settings. This may include default accounts, unnecessary services, exposed management interfaces, or debug modes left active in production environments.
These issues create opportunities for attackers to interact with systems in ways that were not intended. For example, open administrative interfaces or exposed directories can reveal sensitive information or allow unauthorized access.
How to prevent it?
Prevention requires regular review of server and application configurations. Default settings should be removed or updated, unnecessary services should be disabled, and configuration changes should be verified before deployment.
3. A03:2025 Software Supply Chain Failures
Modern applications depend on many external libraries, frameworks, and packages. Software supply chain failures occur when these components contain vulnerabilities or when they are obtained from unsafe sources.
If a dependency is compromised or outdated, attackers may use known weaknesses to target the application. In some cases, malicious packages may also introduce harmful code during the build process.
How to prevent it?
Organizations should maintain an inventory of dependencies used in their applications. Components should be downloaded from trusted repositories, and updates should be monitored to address known security issues.
4. A04:2025 Cryptographic Failures
Cryptographic failures can happen when weak encryption algorithms are used, when encryption keys are stored in insecure locations, or when data is transmitted without proper protection.
Examples include storing passwords in plain text, exposing sensitive data through unencrypted connections, or using outdated cryptographic algorithms. These issues increase the risk of data exposure.
How to prevent it?
Applications should use strong encryption methods for data storage and transmission. Passwords should be securely hashed, encryption keys should be protected, and secure communication protocols should be enforced.
5. A05:2025 Injection
Injection vulnerabilities occur when user input is interpreted as commands by the application or backend systems. Attackers may submit specially crafted inputs to manipulate database queries, system commands, or application logic.
Common examples include SQL injection, command injection, and other cases where input data changes how the system processes requests. These attacks can expose sensitive data or allow unauthorized actions.
How to prevent it?
To prevent injection issues, applications must validate and sanitize user inputs. Parameterized queries should be used for database operations, and APIs should verify input data before processing requests.
6. A06:2025 Insecure Design
Insecure design refers to weaknesses that originate from how the application is planned and structured. Even when code is written correctly, design decisions can create security gaps.
Examples include missing authorization checks, weak account recovery processes, or workflows that allow users to bypass intended restrictions. These problems occur when security checks are not considered during the design stage.
How to prevent it?
Preventing insecure design requires including security considerations during application planning. Teams should review authentication flows, authorization logic, and system interactions before development begins.
7. A07:2025 Authentication Failures
Authentication failures occur when login systems or identity verification processes are not properly implemented. Weak password policies, poor session handling, or missing account protection controls can allow attackers to access user accounts.
Attackers may attempt credential guessing, session misuse, or other techniques to take over accounts. If authentication systems are not properly implemented, these attempts may succeed.
How to prevent it?
To reduce this risk, applications should enforce strong password rules, limit repeated login attempts, and manage sessions securely. Multi-factor authentication can also add an additional layer of verification.
8. A08:2025 Software or Data Integrity Failures
Software or data integrity failures occur when applications do not verify whether code, updates, or data have been modified. Attackers may attempt to tamper with software packages, update processes, or stored data.
For example, if application updates are not verified, malicious code could be introduced during deployment. Unsafe dependency sources can also create similar risks.
How to prevent it?
To prevent this issue, organizations should verify the integrity of software packages and updates. Secure update mechanisms, trusted repositories, and monitoring of build processes help reduce these risks.
9. A09:2025 Security Logging and Alerting Failures
Security logging and alerting failures occur when applications do not record or monitor important security events. Without proper logs, suspicious activity may continue without detection.
Examples include missing login attempt logs, lack of alerts for repeated authentication failures, or insufficient tracking of access to sensitive data. These gaps make it difficult to detect and investigate incidents.
How to prevent it?
Applications should record key security events and store logs securely. Monitoring systems should review these logs and generate alerts when suspicious behavior is detected.
10. A10:2025 Mishandling of Exceptional Conditions
Exceptional conditions refer to errors, unexpected inputs, or unusual system states that occur during application operation. If these situations are not handled properly, the application may expose system details or behave in unintended ways.
Examples include detailed error messages, unhandled exceptions, or debug information visible to users. These responses may reveal internal system information that attackers can use.
How to prevent it?
Applications should handle errors in a controlled manner and avoid exposing technical details in responses. Proper exception handling and controlled error messages help prevent information disclosure.
What’s Next?
After reviewing the OWASP Top 10 vulnerabilities, organizations should begin checking their web applications against these risks. This includes reviewing application code, server configuration, third-party components, authentication logic, and API behavior.
Regular security testing, such as vulnerability assessments and web application penetration testing, can help confirm whether these issues exist. Addressing the findings and reviewing applications during updates or new releases helps keep web systems safer over time.
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