CVE-2024-26503 in Greek Universities Network Open eClass
Summary
by MITRE • 03/15/2024
Unrestricted File Upload vulnerability in Greek Universities Network Open eClass v.3.15 and earlier allows attackers to run arbitrary code via upload of crafted file to certbadge.php endpoint.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/28/2024
The vulnerability identified as CVE-2024-26503 represents a critical unrestricted file upload flaw within the Greek Universities Network Open eClass platform version 3.15 and earlier. This vulnerability resides in the certbadge.php endpoint which fails to properly validate or sanitize file uploads, creating an avenue for malicious actors to bypass security controls and execute arbitrary code on the affected system. The flaw stems from insufficient input validation mechanisms that allow attackers to upload files with potentially dangerous extensions or content without proper authorization checks.
From a technical perspective, this vulnerability aligns with CWE-434 which specifically addresses the issue of unrestricted file upload allowing attackers to execute malicious code through file uploads. The vulnerability operates by permitting attackers to upload crafted files that can contain malicious code or scripts which then get executed in the context of the web server. The certbadge.php endpoint lacks proper file type validation, content inspection, or sanitization processes that would normally prevent the execution of potentially harmful files. Attackers can leverage this flaw to upload web shells, malicious scripts, or other executable content that can be triggered through subsequent requests to the application.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with persistent access to the affected system. Once an attacker successfully uploads a malicious file, they can establish a foothold for further exploitation including privilege escalation, data exfiltration, or use of the compromised system as a pivot point for attacking other systems within the network. This vulnerability directly maps to several ATT&CK techniques including T1190 for exploitation of vulnerabilities and T1059 for execution through command and scripting interpreter. The compromised system can be used to host additional malicious payloads or serve as a command and control server for broader attack operations.
Mitigation strategies for this vulnerability require immediate implementation of proper file upload validation controls. Organizations should implement strict file type validation that whitelists acceptable file extensions and content types while rejecting any uploads that do not conform to predefined security policies. The certbadge.php endpoint must be updated to perform comprehensive content inspection of uploaded files, including MIME type validation and binary signature analysis to detect potentially malicious content. Additionally, uploaded files should be stored in a separate directory with restricted permissions and should not be directly executable from the web root. Regular security updates and patches should be applied to the Open eClass platform to address this vulnerability. Network segmentation and monitoring controls should be implemented to detect suspicious file upload activities and unauthorized access attempts. The vulnerability also highlights the importance of secure coding practices and input validation controls as outlined in OWASP Top Ten and NIST cybersecurity frameworks.