EUVD-2025-15448

Comprehensive Technical Analysis of EUVD-2025-15448

1. Vulnerability Assessment and Severity Evaluation

Vulnerability Description: The vulnerability in Invision Community 5.0.0 before 5.0.7 allows remote code execution (RCE) via crafted template strings to themeeditor.php. The issue is located in the themeeditor controller, specifically within the customCss method, which can be invoked by unauthenticated users. This method passes the value of the content parameter to the Theme::makeProcessFunction() method, leading to the evaluation of arbitrary PHP code by the template engine.

Severity Evaluation:

• Base Score: 10.0 (Critical)
• Base Score Version: CVSS 3.1
• Base Score Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

The CVSS score of 10.0 indicates a critical vulnerability due to the following factors:

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

This vulnerability is highly exploitable and can lead to severe impacts, including full system compromise.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Unauthenticated Access: Attackers can exploit this vulnerability without needing any authentication.
• Remote Code Execution: By crafting malicious template strings, attackers can inject and execute arbitrary PHP code.

Exploitation Methods:

• Crafted Template Strings: Attackers can send specially crafted template strings to the themeeditor.php file, which will be processed by the customCss method.
• PHP Code Injection: The injected PHP code can be executed by the template engine, allowing attackers to perform various malicious actions, such as data exfiltration, system manipulation, and further exploitation.

3. Affected Systems and Software Versions

Affected Software:

• Invision Community versions 5.0.0 through 5.0.6

Affected Systems:

• Any system running the vulnerable versions of Invision Community, including web servers hosting the software.

4. Recommended Mitigation Strategies

Immediate Actions:

• Upgrade: Upgrade to Invision Community version 5.0.7 or later, which addresses this vulnerability.
• Patch Management: Ensure that all software components are up to date with the latest security patches.

Long-Term Mitigations:

• Access Controls: Implement strict access controls and authentication mechanisms to prevent unauthorized access.
• Input Validation: Enhance input validation and sanitization to prevent the injection of malicious code.
• Monitoring: Implement continuous monitoring and logging to detect and respond to suspicious activities.

5. Impact on European Cybersecurity Landscape

Regulatory Compliance:

• Organizations using Invision Community must ensure compliance with relevant regulations, such as GDPR, by addressing this vulnerability promptly.
• Failure to mitigate this vulnerability could result in data breaches, leading to regulatory fines and reputational damage.

Cybersecurity Posture:

• The critical nature of this vulnerability underscores the importance of robust cybersecurity practices, including regular vulnerability assessments and timely patch management.
• European organizations must prioritize cybersecurity to protect against such high-impact vulnerabilities.

6. Technical Details for Security Professionals

Vulnerable Component:

• File: /applications/core/modules/front/system/themeeditor.php
• Method: customCss

Exploitation Details:

• The customCss method can be invoked by unauthenticated users.
• The method passes the content parameter to Theme::makeProcessFunction(), which evaluates the input using the template engine.
• Crafted template strings can be used to inject and execute arbitrary PHP code.

Mitigation Steps:

• Code Review: Conduct a thorough code review to identify and fix similar vulnerabilities in other parts of the application.
• Security Testing: Implement automated security testing to detect and mitigate vulnerabilities during the development lifecycle.
• Incident Response: Develop and maintain an incident response plan to quickly address and mitigate any security incidents.

References:

• Invision Community Release Notes
• Karma Insecurity Advisory
• NVD CVE-2025-47916
• Full Disclosure Mailing List

By addressing this vulnerability promptly and implementing robust cybersecurity measures, organizations can significantly reduce the risk of exploitation and protect their systems and data.