CVE-2017-7684 in OpenMeetings
Summary
by MITRE
Apache OpenMeetings 1.0.0 doesn t check contents of files being uploaded. An attacker can cause a denial of service by uploading multiple large files to the server.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/25/2019
Apache OpenMeetings version 1.0.0 contains a critical security vulnerability classified as CVE-2017-7684 that stems from insufficient validation of uploaded file contents within the application's file handling mechanisms. This flaw represents a classic example of inadequate input validation and sanitization, which falls under the Common Weakness Enumeration category CWE-20. The vulnerability exists because the system fails to implement proper file type checking, size limitations, or content verification during the file upload process, creating an exploitable condition that allows malicious actors to bypass normal security controls.
The technical implementation of this vulnerability enables attackers to upload arbitrary files without proper authorization or validation, specifically targeting the application's file upload functionality. When users upload files through the web interface, the system accepts all file types regardless of their content or intended purpose, which creates a pathway for malicious file execution. This weakness directly enables a denial of service attack scenario where an attacker can consume excessive server resources by uploading multiple large files simultaneously, potentially exhausting disk space, memory, or processing capabilities. The lack of proper file content verification means that even executable files or large binary objects can be uploaded without restriction.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable more sophisticated attacks. While the primary threat manifests as resource exhaustion and service disruption, the absence of file validation creates opportunities for attackers to upload malicious content that could compromise server integrity or facilitate further exploitation. Attackers can leverage this vulnerability to consume server resources at an exponential rate, potentially leading to complete system unavailability for legitimate users. The vulnerability affects the application's availability and integrity, as unauthorized file uploads can disrupt normal operations and potentially provide attackers with persistent access points.
Mitigation strategies for CVE-2017-7684 should focus on implementing comprehensive file validation controls and resource management policies. Organizations should deploy strict file type filtering mechanisms that validate file extensions, MIME types, and actual file content against known safe patterns. The system should enforce size limitations and implement proper file content analysis to prevent execution of potentially malicious files. Additionally, implementing upload quotas, monitoring for unusual upload patterns, and establishing automated alerts for large file transfers can help detect and prevent exploitation attempts. From a security framework perspective, this vulnerability aligns with ATT&CK technique T1195 which covers content injection and T1499 which covers resource hijacking, both of which represent legitimate attack vectors that can be mitigated through proper input validation and access controls. The recommended remediation includes upgrading to a patched version of Apache OpenMeetings where proper file validation mechanisms have been implemented to prevent unauthorized file uploads and protect against resource exhaustion attacks.