EUVD-2025-12661

Comprehensive Technical Analysis of EUVD-2025-12661

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2025-12661 pertains to an unrestricted file upload flaw in ShowDoc, a documentation management system. This vulnerability arises due to inadequate validation of file extensions, allowing attackers to upload and execute arbitrary PHP code, which can lead to remote code execution (RCE).

Severity Evaluation:

• Base Score: 9.4 (Critical)
• Base Score Version: CVSS 4.0
• Base Score Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L

The high base score indicates a critical vulnerability due to the potential for significant impact on confidentiality, integrity, and availability. The attack vector is network-based (AV:N), requires low complexity (AC:L), and does not need user interaction (UI:N). The attacker needs low privileges (PR:L) to exploit this vulnerability, and the impact on confidentiality and integrity is high (VC:H, VI:H), while the impact on availability is low (VA:L).

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Unrestricted File Upload: An attacker can upload a malicious PHP file disguised with a benign file extension.
• Remote Code Execution (RCE): Once the malicious file is uploaded, the attacker can execute arbitrary PHP code, leading to full control over the server.

Exploitation Methods:

• File Upload: The attacker uploads a PHP file with a crafted extension that bypasses the validation checks.
• Code Execution: The attacker triggers the execution of the uploaded PHP file, gaining control over the server.

3. Affected Systems and Software Versions

Affected Software:

• ShowDoc: All versions before 2.8.7

Affected Systems:

• Any system running the vulnerable versions of ShowDoc, including web servers and documentation management platforms.

4. Recommended Mitigation Strategies

Immediate Actions:

• Update Software: Upgrade to ShowDoc version 2.8.7 or later, which includes the necessary patches to mitigate this vulnerability.
• Temporary Mitigation: Implement strict file upload policies and validation mechanisms to prevent the upload of executable files.

Long-Term Strategies:

• Regular Patching: Ensure that all software, including ShowDoc, is regularly updated to the latest versions.
• Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate potential vulnerabilities.
• Intrusion Detection: Deploy intrusion detection systems (IDS) to monitor for suspicious activities and potential exploitation attempts.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations using ShowDoc, particularly those in the European Union. Given the critical nature of the vulnerability, it could lead to data breaches, unauthorized access, and potential disruption of services. The impact on confidentiality and integrity is particularly concerning, as it could result in the exposure of sensitive information and the compromise of critical systems.

6. Technical Details for Security Professionals

Vulnerability Details:

• Cause: Improper validation of file extensions during the file upload process.
• Effect: Allows the execution of arbitrary PHP code, leading to RCE.

Exploitation Steps:

1. Identify Target: Locate a system running a vulnerable version of ShowDoc.
2. Craft Malicious File: Create a PHP file with a crafted extension that bypasses validation.
3. Upload File: Upload the malicious file through the ShowDoc file upload feature.
4. Execute Code: Trigger the execution of the uploaded PHP file to gain control over the server.

References:

• GitHub Vulnerability Repository
• ShowDoc GitHub Pull Request
• CNVD Vulnerability Details
• NVD CVE Details

Aliases:

• CVE-2025-0520

Assigner:

• VulnCheck

ENISA IDs:

• Product: 8ea3fe1d-f6bb-3c5d-8f84-492f5ddaf0d5 (ShowDoc, versions 0 <2.8.7)
• Vendor: 5e6e9000-1747-3e18-9762-4f38c8bfda74 (ShowDoc)

By addressing this vulnerability promptly and implementing robust security measures, organizations can significantly reduce the risk of exploitation and protect their critical assets.