EUVD-2025-204602

Comprehensive Technical Analysis of EUVD-2025-204602

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2025-204602 pertains to an unrestricted file upload flaw in InnovaStudio WYSIWYG Editor version 5.4. This vulnerability allows attackers to bypass file extension restrictions through filename manipulation, enabling the upload of malicious ASP shells. The severity of this vulnerability is rated with a CVSS base score of 9.3, indicating a critical risk. The CVSS vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N highlights the following:

• Attack Vector (AV:N): Network-based attack.
• Attack Complexity (AC:L): Low complexity required for exploitation.
• Authentication (AT:N): No authentication required.
• Privileges Required (PR:N): No privileges required.
• User Interaction (UI:N): No user interaction required.
• Confidentiality Impact (VC:H): High impact on confidentiality.
• Integrity Impact (VI:H): High impact on integrity.
• Availability Impact (VA:H): High impact on availability.

2. Potential Attack Vectors and Exploitation Methods

Attackers can exploit this vulnerability by:

• Filename Manipulation: Using techniques such as null byte injection or alternate file extensions to bypass the file upload restrictions.
• Malicious File Upload: Uploading ASP shells or other malicious files that can execute arbitrary code on the server.
• Remote Code Execution (RCE): Once the malicious file is uploaded, attackers can execute commands on the server, leading to full system compromise.

3. Affected Systems and Software Versions

The vulnerability affects:

• Product: InnovaStudio WYSIWYG Editor
• Versions: All versions up to and including 5.4

4. Recommended Mitigation Strategies

To mitigate this vulnerability, the following steps are recommended:

• Update Software: Upgrade to a patched version of InnovaStudio WYSIWYG Editor if available.
• Input Validation: Implement robust input validation and sanitization for file uploads.
• File Type Restrictions: Enforce strict file type and extension checks.
• Content Security Policies: Implement Content Security Policies (CSP) to mitigate the impact of successful exploitation.
• Regular Audits: Conduct regular security audits and vulnerability assessments.
• Monitoring: Implement continuous monitoring for suspicious file upload activities.

5. Impact on European Cybersecurity Landscape

The impact of this vulnerability on the European cybersecurity landscape is significant due to the widespread use of WYSIWYG editors in web applications. Unrestricted file upload vulnerabilities can lead to data breaches, unauthorized access, and system compromises, affecting the confidentiality, integrity, and availability of information systems. Organizations across Europe must prioritize patching and securing their web applications to prevent potential exploitation.

6. Technical Details for Security Professionals

Exploitation Details:

• Null Byte Injection: Attackers can append null bytes (%00) to file names to bypass extension checks.
• Alternate File Extensions: Using file extensions that are not explicitly restricted, such as .asp;.jpg.

Detection and Response:

• Log Analysis: Monitor server logs for unusual file upload activities.
• Intrusion Detection Systems (IDS): Deploy IDS to detect and alert on suspicious file upload patterns.
• Incident Response Plan: Develop and maintain an incident response plan to quickly address any detected exploitation attempts.

References:

• NVD Entry
• InnovaStudio Official Website
• Exploit Database Entry
• VulnCheck Advisory

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