EUVD-2024-27585

Comprehensive Technical Analysis of EUVD-2024-27585

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2024-27585, also known as CVE-2024-2636, is classified as an "Unrestricted Upload of File" vulnerability affecting Cegid Meta4 HR. This vulnerability allows an attacker to upload malicious files to the server via the '/config/espanol/update_password.jsp' file by modifying the 'M4_NEW_PASSWORD' parameter. The severity of this vulnerability is rated with a CVSS Base Score of 9.0, indicating a critical risk.

The CVSS vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H breaks down as follows:

• AV:N - Attack Vector: Network
• AC:H - Attack Complexity: High
• PR:N - Privileges Required: None
• UI:N - User Interaction: None
• S:C - Scope: Changed
• C:H - Confidentiality Impact: High
• I:H - Integrity Impact: High
• A:H - Availability Impact: High

This high severity score is due to the potential for complete system compromise, including high impacts on confidentiality, integrity, and availability.

2. Potential Attack Vectors and Exploitation Methods

The primary attack vector involves exploiting the unrestricted file upload functionality. An attacker can:

1. Upload a Malicious JSP File: By modifying the 'M4_NEW_PASSWORD' parameter, an attacker can upload a JSP file containing malicious code.
2. Execute the Malicious Code: When the application loads the malicious JSP file, the embedded code is executed, potentially leading to remote code execution (RCE).

Possible exploitation methods include:

• Web Shell Upload: Uploading a web shell to gain persistent access to the server.
• Data Exfiltration: Executing commands to exfiltrate sensitive data.
• Lateral Movement: Using the compromised server as a pivot point to attack other systems within the network.

3. Affected Systems and Software Versions

The vulnerability affects the following versions of Cegid Meta4 HR:

• Meta4 HR Version 819.001.022
• Other unspecified versions of Meta4 HR

Organizations using these versions are at risk and should prioritize applying patches or mitigations.

4. Recommended Mitigation Strategies

To mitigate the risk associated with this vulnerability, the following strategies are recommended:

1. Patch Management: Apply the latest security patches provided by Cegid.
2. Input Validation: Implement strict input validation and sanitization for file uploads.
3. Access Controls: Restrict access to the '/config/espanol/update_password.jsp' endpoint to authorized users only.
4. File Upload Restrictions: Enforce file type and size restrictions for uploads.
5. Monitoring and Logging: Enable comprehensive logging and monitoring to detect and respond to suspicious activities.
6. Web Application Firewall (WAF): Deploy a WAF to filter out malicious upload attempts.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations using Cegid Meta4 HR, particularly within the European Union. Given the critical nature of HR systems, a successful exploit could lead to:

• Data Breaches: Compromise of sensitive employee data.
• Operational Disruption: Interruption of HR services and processes.
• Compliance Issues: Violation of data protection regulations such as GDPR.

The European cybersecurity landscape must prioritize addressing this vulnerability to prevent widespread impacts on affected organizations.

6. Technical Details for Security Professionals

For security professionals, the following technical details are pertinent:

• Vulnerable Endpoint: '/config/espanol/update_password.jsp'
• Parameter to Modify: 'M4_NEW_PASSWORD'
• Potential Payload: A JSP file with embedded malicious code.
• Detection: Monitor for unusual file upload activities and unexpected JSP file executions.
• Response: Implement incident response plans to quickly detect and mitigate any exploitation attempts.

References:

• INCIBE Notice on Multiple Vulnerabilities in Meta4 HR

By addressing this vulnerability promptly and effectively, organizations can significantly reduce the risk of a successful attack and maintain the integrity and security of their HR systems.