EUVD-2025-21031

Comprehensive Technical Analysis of EUVD-2025-21031

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2025-21031 is an OS command injection flaw in Mako Server versions 2.5 and 2.6. This vulnerability allows an unauthenticated attacker to execute arbitrary commands on the underlying operating system by exploiting the examples/save.lsp endpoint. 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): Network (N) - The vulnerability is exploitable over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal skill or resources.
• Authentication (AT): None (N) - No authentication is required to exploit the vulnerability.
• Privileges Required (PR): None (N) - No special privileges are needed.
• User Interaction (UI): None (N) - No user interaction is required.
• Confidentiality (VC): High (H) - Complete loss of confidentiality.
• Integrity (VI): High (H) - Complete loss of integrity.
• Availability (VA): High (H) - Complete loss of availability.

2. Potential Attack Vectors and Exploitation Methods

The primary attack vector involves sending a crafted PUT request to the examples/save.lsp endpoint, embedding malicious Lua code that leverages the os.execute() function. This code is then persisted on disk and executed via a subsequent GET request to examples/manage.lsp. This allows for remote command execution, enabling the attacker to:

• Execute arbitrary commands on the server.
• Gain unauthorized access to sensitive data.
• Compromise the integrity of the system.
• Disrupt services by deleting files or modifying configurations.

3. Affected Systems and Software Versions

The vulnerability affects Mako Server versions 2.5 and 2.6, impacting both Windows and Unix-based deployments. Organizations using these versions are at risk and should prioritize mitigation efforts.

4. Recommended Mitigation Strategies

To mitigate this vulnerability, the following steps are recommended:

• Upgrade to a Patched Version: Ensure that Mako Server is updated to a version that addresses this vulnerability.
• Disable Unnecessary Endpoints: If the examples/save.lsp and examples/manage.lsp endpoints are not required, disable them.
• Implement Input Validation: Ensure that all input is properly validated and sanitized to prevent command injection.
• Network Segmentation: Isolate critical systems and limit network access to the Mako Server.
• Monitoring and Logging: Implement robust monitoring and logging to detect and respond to suspicious activities.
• Regular Security Audits: Conduct regular security audits and vulnerability assessments to identify and address potential risks.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations within the European Union, particularly those relying on Mako Server for critical operations. The potential for unauthenticated remote command execution can lead to data breaches, service disruptions, and financial losses. This underscores the importance of timely patching and adherence to best security practices to protect against such threats.

6. Technical Details for Security Professionals

Exploitation Details:

• PUT Request: The attacker sends a PUT request to examples/save.lsp with a payload containing malicious Lua code.
• Persistence: The malicious code is saved to disk.
• Execution: A subsequent GET request to examples/manage.lsp triggers the execution of the saved code.

Example Payload:

os.execute("rm -rf /")

Detection:

• Network Traffic Analysis: Monitor for unusual PUT and GET requests to the specified endpoints.
• File Integrity Monitoring: Check for unauthorized modifications to files associated with the examples directory.
• Log Analysis: Review server logs for suspicious activities and command executions.

References:

• Metasploit Module
• Exploit Database
• VulnCheck Advisory

Conclusion: The OS command injection vulnerability in Mako Server versions 2.5 and 2.6 is critical and requires immediate attention. Organizations should prioritize updating to a patched version and implementing robust security measures to mitigate the risk. Continuous monitoring and regular security assessments are essential to maintain a strong cybersecurity posture.