EUVD-2024-38297

Comprehensive Technical Analysis of EUVD-2024-38297

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2024-38297 is an authenticated Remote Code Execution (RCE) in Thruk, a multibackend monitoring web interface for Naemon, Nagios, Icinga, and Shinken. The vulnerability allows authorized users with network access to inject arbitrary commands via the URL parameter during PDF report generation. This issue is critical due to the potential for complete system compromise.

Severity Evaluation:

• CVSS Base Score: 10.0 (Critical)
• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
  • Attack Vector (AV): Network (N)
  • Attack Complexity (AC): Low (L)
  • Privileges Required (PR): Low (L)
  • User Interaction (UI): None (N)
  • Scope (S): Changed (C)
  • Confidentiality (C): High (H)
  • Integrity (I): High (H)
  • Availability (A): High (H)

The high CVSS score indicates the severity of the vulnerability, emphasizing the need for immediate attention and mitigation.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Authenticated RCE: An attacker with valid credentials can exploit the vulnerability by injecting malicious commands into the URL parameter during PDF report generation.
• Network Access: The attacker must have network access to the Thruk web interface.

Exploitation Methods:

• Command Injection: The attacker can craft a URL with embedded commands that will be executed by the /script/html2pdf.sh script.
• Payload Delivery: The payload can be delivered through the URL parameter, which is not properly sanitized by the Thruk application.

3. Affected Systems and Software Versions

Affected Systems:

• Thruk versions prior to 3.16.

Software Versions:

• All versions of Thruk below 3.16 are vulnerable. Users are advised to upgrade to version 3.16 or later to mitigate the risk.

4. Recommended Mitigation Strategies

Immediate Actions:

• Upgrade: Upgrade Thruk to version 3.16 or later, which addresses the vulnerability.
• Access Control: Restrict access to the Thruk web interface to trusted users only.
• Monitoring: Implement monitoring and logging to detect any suspicious activities related to PDF report generation.

Long-Term Strategies:

• Regular Patching: Ensure that all software components are regularly updated and patched.
• Security Audits: Conduct regular security audits and vulnerability assessments.
• Input Validation: Implement robust input validation and sanitization mechanisms to prevent similar vulnerabilities in the future.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations using Thruk for monitoring their IT infrastructure. Given the widespread use of monitoring tools like Thruk in various sectors, including healthcare, finance, and government, the potential impact is substantial. Unauthorized access and command execution can lead to data breaches, service disruptions, and loss of sensitive information, affecting the overall cybersecurity posture of European organizations.

6. Technical Details for Security Professionals

Vulnerability Details:

• CVE ID: CVE-2024-39915
• Vulnerable Component: The /script/html2pdf.sh script used for PDF report generation.
• Exploitation: The vulnerability is exploited by injecting commands into the URL parameter, which are then executed by the script.

Mitigation Steps:

1. Upgrade Thruk: Ensure that all instances of Thruk are upgraded to version 3.16 or later.
2. Input Sanitization: Implement additional input sanitization for the URL parameter to prevent command injection.
3. Access Controls: Enforce strict access controls to limit the number of users with access to the reporting functionality.
4. Monitoring and Logging: Set up monitoring and logging to detect and respond to any suspicious activities related to PDF report generation.

References:

• GitHub Security Advisory
• GitHub Commit

By following these recommendations, organizations can effectively mitigate the risk posed by this vulnerability and enhance their overall cybersecurity posture.