Mass assignment vulnerabilities occur when an application automatically binds user input to internal object properties without proper validation. This can unintentionally expose sensitive fields, allowing attackers to manipulate API requests and modify data that should be restricted. For example, an attacker could modify a user's role or access control settings by including unexpected parameters in their request. Such vulnerabilities can lead to unauthorized data access, privilege escalation, and potential data corruption. hexadius.com
To mitigate mass assignment vulnerabilities, developers should implement strict input validation and explicitly define which fields can be updated. This involves allowing only specific fields to be updated by the client and enforcing authentication and authorization checks to ensure users can modify only their own data. Disabling auto-binding and using schema validation tools can further enhance security. Regular security testing is also crucial to identify and patch potential vulnerabilities. hexadius.com