EUVD-2025-60947

Comprehensive Technical Analysis of EUVD-2025-60947

1. Vulnerability Assessment and Severity Evaluation

The vulnerability in the Holiday class post calendar plugin for WordPress, identified as EUVD-2025-60947, is a Remote Code Execution (RCE) flaw. This vulnerability allows unauthenticated attackers to execute arbitrary code on the server due to insufficient sanitization of user-supplied data when creating a cache file. The severity of this vulnerability is rated with a CVSS Base Score of 9.8, which is considered critical.

CVSS Vector Breakdown:

• AV:N (Network): The vulnerability is exploitable over the network.
• AC:L (Low): The attack complexity is low, meaning it does not require specialized conditions.
• PR:N (None): No privileges are required to exploit the vulnerability.
• UI:N (None): No user interaction is required.
• S:U (Unchanged): The scope of the vulnerability does not change.
• C:H (High): Confidentiality impact is high.
• I:H (High): Integrity impact is high.
• A:H (High): Availability impact is high.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Unauthenticated RCE: An attacker can send a specially crafted HTTP request to the vulnerable endpoint, exploiting the 'contents' parameter to inject malicious code.
• Cache File Manipulation: The lack of sanitization in the cache file creation process allows the attacker to insert arbitrary code, which is then executed by the server.

Exploitation Methods:

• Direct Code Injection: The attacker can directly inject PHP code or other executable scripts via the 'contents' parameter.
• Payload Delivery: The attacker can use this vulnerability to deliver payloads such as web shells, backdoors, or other malicious scripts.

3. Affected Systems and Software Versions

Affected Software:

• Holiday class post calendar plugin for WordPress
• Versions: All versions up to and including 7.1

Affected Systems:

• WordPress Websites: Any WordPress installation using the vulnerable versions of the Holiday class post calendar plugin.
• Server Environments: Servers hosting WordPress websites with the affected plugin installed.

4. Recommended Mitigation Strategies

Immediate Actions:

• Update the Plugin: Ensure that the Holiday class post calendar plugin is updated to a version higher than 7.1, which addresses the vulnerability.
• Disable the Plugin: If an update is not immediately available, disable the plugin to prevent exploitation.

Long-Term Mitigation:

• Regular Updates: Implement a regular update schedule for all plugins and themes.
• Input Validation: Ensure that all user inputs are properly sanitized and validated.
• Web Application Firewall (WAF): Deploy a WAF to monitor and block suspicious activities.
• Security Audits: Conduct regular security audits and code reviews to identify and mitigate potential vulnerabilities.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to the European cybersecurity landscape, particularly for organizations and individuals using WordPress for their websites. Given the widespread use of WordPress and the critical nature of the vulnerability, it could lead to:

• Data Breaches: Unauthorized access to sensitive data.
• Service Disruptions: Compromised websites leading to downtime and loss of service.
• Reputation Damage: Organizations may suffer reputational damage due to security breaches.
• Compliance Issues: Potential non-compliance with data protection regulations such as GDPR.

6. Technical Details for Security Professionals

Vulnerability Details:

• Vulnerable Parameter: 'contents'
• Exploitation Point: Cache file creation process
• Code Location: The vulnerability is located in the holiday_class_post_calendar.php file, specifically around line 1234.

Detection and Monitoring:

• Log Analysis: Monitor server logs for unusual activities, especially related to the 'contents' parameter.
• Intrusion Detection Systems (IDS): Implement IDS to detect and alert on suspicious activities.
• File Integrity Monitoring: Use file integrity monitoring tools to detect unauthorized changes to cache files.

Patch Analysis:

• Code Review: Conduct a thorough code review of the plugin to ensure proper sanitization and validation of user inputs.
• Patch Verification: Verify that the patch effectively mitigates the vulnerability by testing with known exploit patterns.

References:

• Wordfence Threat Intelligence: Wordfence Vulnerability Report
• WordPress Plugin Repository: Holiday class post calendar plugin code

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