CVE-2020-36877 in Serious Play F3 Media Server
Summary
by MITRE • 12/05/2025
ReQuest Serious Play F3 Media Server 7.0.3 contains an unauthenticated remote code execution vulnerability that allows attackers to execute arbitrary commands as the web server user. Attackers can upload PHP executable files via the Quick File Uploader page, resulting in remote code execution on the server.
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Analysis
by VulDB Data Team • 12/06/2025
The ReQuest Serious Play F3 Media Server version 7.0.3 presents a critical unauthenticated remote code execution vulnerability that fundamentally compromises the security posture of affected systems. This vulnerability resides within the Quick File Uploader page functionality, which lacks proper authentication mechanisms and input validation controls. The flaw allows malicious actors to bypass authentication requirements and directly upload PHP executable files to the server, creating a persistent backdoor for remote command execution. Such a vulnerability represents a severe oversight in the application's security architecture, as it eliminates the basic requirement for user authentication before permitting file upload operations.
The technical exploitation of this vulnerability follows a straightforward yet dangerous methodology that leverages the absence of proper access controls and file validation. Attackers can directly submit malicious PHP payloads through the exposed upload interface without requiring any valid credentials or session tokens. Once uploaded, these PHP files can be executed by the web server with the privileges of the web application user, typically a low-privileged account but still capable of executing commands within the server's operational context. This execution model aligns with common attack patterns documented in the attack framework, where initial access is gained through web application vulnerabilities leading to privilege escalation and system compromise.
The operational impact of this vulnerability extends far beyond simple command execution, as it provides attackers with comprehensive control over the affected media server infrastructure. The web server user context typically grants access to the server's file system, database connections, and network interfaces, enabling attackers to exfiltrate sensitive data, deploy additional malware, or establish persistent access points. This vulnerability directly violates the principle of least privilege and demonstrates a critical failure in implementing proper authorization controls. The exposure of such a flaw in a media server application is particularly concerning as these systems often handle sensitive content and may be integrated with other enterprise systems, potentially serving as a stepping stone for broader network compromise.
Security professionals should recognize this vulnerability as a clear violation of multiple security standards including cwe-22 which addresses improper limitation of a pathname to a restricted directory, and cwe-434 which covers insecure file upload. The absence of proper file type validation, directory restriction, and authentication requirements creates an environment where attackers can easily gain unauthorized access. Mitigation strategies should include immediate patching of the affected software version, implementation of strict file upload validation controls, and enforcement of mandatory authentication for all administrative functions. Network segmentation and firewall rules should be implemented to restrict access to upload interfaces, while regular security audits should verify that no unauthorized upload capabilities exist within the application. Additionally, the principle of defense in depth should be applied through monitoring for suspicious file upload activities and implementing web application firewalls to detect and block malicious payload submissions. The vulnerability also highlights the importance of secure coding practices and regular security assessments to prevent similar issues in future software deployments.