EUVD-2024-54104

Comprehensive Technical Analysis of EUVD-2024-54104

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2024-54104 pertains to PHP Object Injection in the CozyStay and TinySalt plugins for WordPress. This vulnerability arises from the deserialization of untrusted input in the 'ajax_handler' function. The severity of this vulnerability is rated with a CVSS Base Score of 9.8, which is considered critical. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H indicates the following:

• Attack Vector (AV): Network (N) - The vulnerability is exploitable over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal skill or resources.
• Privileges Required (PR): None (N) - No authentication is required to exploit the vulnerability.
• User Interaction (UI): None (N) - No user interaction is required.
• Scope (S): Unchanged (U) - The vulnerability does not affect resources beyond the security scope managed by the security authority.
• Confidentiality (C): High (H) - There is a high impact on the confidentiality of the system.
• Integrity (I): High (H) - There is a high impact on the integrity of the system.
• Availability (A): High (H) - There is a high impact on the availability of the system.

2. Potential Attack Vectors and Exploitation Methods

The primary attack vector involves unauthenticated attackers exploiting the PHP Object Injection vulnerability by sending crafted input to the 'ajax_handler' function. The deserialization of this input can lead to the injection of a PHP Object. Although no known Property-Oriented Programming (POP) chain is present in the vulnerable software itself, the presence of a POP chain in another installed plugin or theme can significantly amplify the risk. Potential exploitation methods include:

• Arbitrary File Deletion: If a POP chain allows it, attackers could delete critical system files.
• Sensitive Data Retrieval: Attackers could exfiltrate sensitive data from the server.
• Code Execution: In the worst-case scenario, attackers could execute arbitrary code on the server.

3. Affected Systems and Software Versions

The vulnerability affects:

• CozyStay - Hotel Booking WordPress Theme: All versions up to and including 1.7.0.
• TinySalt - Personal Food Blog WordPress Theme: All versions up to and including 3.9.0.

4. Recommended Mitigation Strategies

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

• Update Software: Immediately update the CozyStay and TinySalt plugins to versions that address this vulnerability.
• Disable Unnecessary Plugins: Remove or disable any unnecessary plugins or themes that could introduce a POP chain.
• Implement Input Validation: Ensure that all input is properly validated and sanitized to prevent deserialization of untrusted data.
• Regular Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate potential risks.
• Use Security Plugins: Employ security plugins like Wordfence to monitor and protect against such vulnerabilities.

5. Impact on European Cybersecurity Landscape

The impact of this vulnerability on the European cybersecurity landscape is significant due to the widespread use of WordPress and its plugins. The critical nature of the vulnerability means that unpatched systems are at high risk of being compromised, leading to potential data breaches, service disruptions, and other security incidents. Organizations and individuals using the affected plugins should prioritize updating their systems to mitigate this risk.

6. Technical Details for Security Professionals

For security professionals, the following technical details are pertinent:

• Vulnerable Function: The 'ajax_handler' function in the CozyStay and TinySalt plugins is the point of vulnerability.
• Deserialization Issue: The vulnerability stems from the deserialization of untrusted input, which can lead to PHP Object Injection.
• POP Chain Dependency: Although the vulnerability itself does not contain a POP chain, the presence of a POP chain in other installed plugins or themes can exacerbate the risk.
• Detection and Monitoring: Implement logging and monitoring to detect any unusual activity related to the 'ajax_handler' function. Use intrusion detection systems (IDS) and intrusion prevention systems (IPS) to monitor for suspicious network traffic.
• Patch Management: Ensure that a robust patch management process is in place to quickly apply updates and patches as they become available.

Conclusion

The PHP Object Injection vulnerability in the CozyStay and TinySalt plugins for WordPress is a critical issue that requires immediate attention. By understanding the technical details and implementing the recommended mitigation strategies, organizations can significantly reduce the risk of exploitation and protect their systems from potential attacks.

References

• Wordfence Threat Intel
• CozyStay Changelog
• TinySalt Changelog