CVE-2018-11776 identifies a critical remote code execution vulnerability in Apache Struts framework versions 2.3 through 2.3.34 and 2.5 through 2.5.16 that enables attackers to execute arbitrary code through namespace manipulation. This vulnerability achieves a CVSS score of 8.1 (High severity) and represents a significant threat to Java web applications utilizing affected Struts versions with specific namespace configurations. The vulnerability details reveal that when alwaysSelectFullNamespace is enabled (either manually or through plugins like Convention Plugin), applications become susceptible to remote code execution when using results with no namespace while upper actions have no or wildcard namespace configurations. This creates substantial exploit risk for enterprise Java applications that rely on Apache Struts for MVC architecture, particularly affecting systems using dynamic namespace handling, URL tag processing, and applications implementing the Convention Plugin for annotation-based configuration management. The technical root cause lies in Apache Struts' improper handling of namespace resolution when alwaysSelectFullNamespace is activated, where the framework fails to properly validate namespace boundaries, creating a vector for known exploited vulnerabilities targeting Java web applications. The vulnerability specifically affects two attack scenarios: results processing with undefined namespaces in conjunction with wildcard upper package namespaces, and URL tag manipulation where tags lack value and action attributes while residing in packages with permissive namespace configurations. The widespread use of Apache Struts in enterprise environments makes this vulnerability particularly concerning for organizations running legacy Java applications. Mitigation steps require upgrading to Apache Struts versions 2.3.35 or 2.5.17 and later, which implement proper namespace validation and prevent unauthorized code execution through namespace manipulation. Organizations should prioritize identifying all applications using vulnerable Struts versions, review namespace configurations for wildcard usage, disable alwaysSelectFullNamespace where not required, implement strict input validation for URL parameters, and maintain updated CVE database records to track similar framework vulnerabilities that could compromise Java web application security through improper input handling and namespace resolution attacks.