CVE-2006-1547 identifies a denial of service vulnerability in Apache Struts ActionForm before version 1.2.9 that enables attackers to disrupt application availability through malicious multipart/form-data parameter manipulation. This vulnerability achieves a CVSS score of 7.5 (High severity) targeting the availability component specifically, indicating significant potential for service disruption in web applications using vulnerable Struts versions with BeanUtils 1.7. The vulnerability details reveal that ActionForm's public getMultipartRequestHandler method provides unauthorized access to CommonsMultipartRequestHandler implementation internals, allowing remote attackers to craft multipart/form-data encoded forms with parameter names that reference dangerous methods and manipulate request handling mechanisms. This creates substantial exploit risk for Java web applications utilizing Apache Struts for form processing and file uploads, particularly affecting enterprise applications that handle user-submitted multipart data through Struts ActionForm components without proper parameter validation and access controls. The technical root cause lies in Apache Struts' flawed combination of exposed public methods and insufficient input validation, where the getMultipartRequestHandler method creates an attack surface that enables parameter injection through BeanUtils reflection-based population mechanisms, creating a vector for known exploited vulnerabilities targeting Java web frameworks. The vulnerability specifically affects the interaction between ActionForm's processPopulate method and BeanUtils' reflection capabilities, where unvalidated parameter names can reference internal multipart request handler properties and manipulate resource allocation or processing logic to achieve denial of service conditions. This represents a classic example of improper input validation (CWE-20) combined with exposed dangerous functionality, highlighting the security risks of reflection-based parameter binding in web frameworks. Mitigation steps require upgrading to Apache Struts version 1.2.9 or later, which addresses the parameter validation issues and restricts access to dangerous internal methods through improved input sanitization and method exposure controls. Organizations should prioritize identifying all applications using vulnerable Struts versions, implement strict parameter validation for multipart form processing, review form handling code for similar reflection-based vulnerabilities, and maintain updated CVE database records to track similar denial of service vulnerabilities that could compromise web application availability through parameter injection and method access manipulation attacks in Java web frameworks.