EUVD-2025-21028

Comprehensive Technical Analysis of EUVD-2025-21028

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2025-21028 is an unrestricted file upload vulnerability in BuilderEngine 3.5.0, facilitated by the integration of the elFinder 2.0 file manager and its use of the jQuery File Upload plugin. This vulnerability allows an attacker to upload a malicious .php file and execute arbitrary PHP code on the server. The severity of this vulnerability is rated with a CVSS base score of 9.3, indicating a critical risk.

CVSS Vector Breakdown:

• AV:N (Network Vector): The vulnerability is exploitable over the network.
• AC:L (Low Complexity): The attack requires low skill or resources.
• AT:N (No Authentication): No authentication is required to exploit the vulnerability.
• PR:N (No Privileges Required): No privileges are required to exploit the vulnerability.
• UI:N (No User Interaction): No user interaction is required to exploit the vulnerability.
• VC:H (High Confidentiality Impact): The vulnerability has a high impact on confidentiality.
• VI:H (High Integrity Impact): The vulnerability has a high impact on integrity.
• VA:H (High Availability Impact): The vulnerability has a high impact on availability.
• SC:N (No Scope Change): The vulnerability does not change the security scope.
• SI:N (No Scope Change): The vulnerability does not change the security scope.
• SA:N (No Scope Change): The vulnerability does not change the security scope.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Unauthenticated File Upload: An attacker can upload a malicious .php file without needing any authentication.
• Remote Code Execution (RCE): Once the malicious file is uploaded, the attacker can execute arbitrary PHP code on the server.

Exploitation Methods:

• Direct Exploitation: The attacker can directly upload a .php file containing malicious code through the file upload functionality provided by the jQuery File Upload plugin.
• Automated Exploitation: Exploit scripts and frameworks like Metasploit can be used to automate the exploitation process, making it easier for attackers to compromise multiple systems.

3. Affected Systems and Software Versions

Affected Systems:

• BuilderEngine CMS Version 3.5.0: Systems running this specific version of BuilderEngine are vulnerable.
• elFinder 2.0 File Manager: The integration of this file manager with the jQuery File Upload plugin exposes the vulnerability.

Software Versions:

• BuilderEngine 3.5.0
• elFinder 2.0
• jQuery File Upload Plugin

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Patching: Apply the latest security patches provided by BuilderEngine to address the vulnerability.
• Access Controls: Implement strict access controls to restrict file upload functionality to authenticated users only.
• File Validation: Enforce proper file validation and type restrictions to prevent the upload of malicious files.

Long-Term Mitigation:

• Regular Updates: Ensure that all software components, including BuilderEngine, elFinder, and jQuery plugins, are regularly updated to the latest versions.
• Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate potential vulnerabilities.
• Web Application Firewalls (WAF): Deploy WAFs to monitor and block suspicious file upload activities.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations using BuilderEngine CMS within the European Union. Given the critical nature of the vulnerability, it can lead to data breaches, unauthorized access, and potential disruption of services. The impact on confidentiality, integrity, and availability of affected systems is high, making it a priority for cybersecurity professionals to address promptly.

6. Technical Details for Security Professionals

Technical Overview:

• Vulnerability Type: Unrestricted File Upload leading to Remote Code Execution (RCE).
• Root Cause: Improper validation and restriction of file types and locations during upload operations in the jQuery File Upload plugin, exacerbated by BuilderEngine’s lack of access controls.
• Exploit Path: The attacker can upload a .php file with malicious code via the file upload functionality and execute it on the server.

Detection and Response:

• Log Analysis: Monitor server logs for unusual file upload activities and PHP execution requests.
• Intrusion Detection Systems (IDS): Implement IDS to detect and alert on suspicious file upload patterns.
• Incident Response: Develop an incident response plan to quickly identify, contain, and remediate any successful exploitation attempts.

References:

• Metasploit Module: BuilderEngine Upload Exec
• Exploit Database: Exploit-DB Entry
• Support Documentation: AlertLogic Support
• Vulnerability Advisory: VulnCheck Advisory

By addressing this vulnerability promptly and implementing robust mitigation strategies, organizations can significantly reduce the risk of exploitation and protect their systems from potential cyber threats.