CVE-2025-66262

Comprehensive Technical Analysis of CVE-2025-66262

1. Vulnerability Assessment and Severity Evaluation

CVE ID: CVE-2025-66262

Description: The vulnerability involves an arbitrary file overwrite via a path traversal issue during tar extraction in the restore_mozzi_memories.sh script used by DB Electronica Telecomunicazioni S.p.A. Mozart FM Transmitter. This script extracts user-controlled tar archives with the -C / flag, allowing an attacker to deposit contents to the filesystem root without proper path validation.

Severity: The CVSS score of 9.8 indicates a critical vulnerability. This high score is due to the potential for full system compromise, the ease of exploitation, and the lack of authentication required to exploit the vulnerability.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

1. Unauthenticated File Upload: Attackers can exploit unauthenticated file upload vulnerabilities (CVE-01, CVE-06, CVE-07) to upload malicious .tgz archives.
2. Path Traversal: The malicious archives can contain path-traversed filenames (e.g., etc/shadow, var/www/index.php) to overwrite critical system files.
3. Arbitrary File Overwrite: The restore_mozzi_memories.sh script extracts these archives to the filesystem root, allowing attackers to overwrite files in writable directories.

Exploitation Methods:

1. Crafting Malicious Archives: Attackers can create .tgz archives with path-traversed filenames.
2. Uploading Archives: These archives are uploaded using the unauthenticated file upload vulnerabilities.
3. Extraction and Overwrite: The restore_mozzi_memories.sh script extracts these archives, overwriting critical system files and achieving full system compromise.

3. Affected Systems and Software Versions

Affected Systems:

• DB Electronica Telecomunicazioni S.p.A. Mozart FM Transmitter

Affected Versions:

• Versions 30, 50, 100, 300, 500, 1000, 2000, 3000, 3500, 6000, 7000

4. Recommended Mitigation Strategies

1. Patch Management:

   • Apply the latest patches and updates provided by DB Electronica Telecomunicazioni S.p.A.

2. Input Validation:

   • Implement strict input validation for file uploads to prevent unauthenticated file uploads.

3. Path Validation:

   • Modify the restore_mozzi_memories.sh script to include path validation before extracting archives.

4. Access Controls:

   • Enforce strict access controls and authentication mechanisms for file uploads and script execution.

5. Monitoring and Logging:

   • Implement robust monitoring and logging to detect and respond to suspicious activities related to file uploads and extraction processes.

6. Backup and Recovery:

   • Ensure regular backups and have a recovery plan in place to restore critical system files in case of compromise.

5. Impact on Cybersecurity Landscape

Immediate Impact:

• Full system compromise of affected Mozart FM Transmitters.
• Potential disruption of telecommunication services.
• Unauthorized access to sensitive data and configurations.

Long-term Impact:

• Increased awareness of the risks associated with unauthenticated file uploads and improper path validation.
• Emphasis on the importance of secure coding practices and regular security audits.
• Potential regulatory and compliance implications for organizations using affected systems.

6. Technical Details for Security Professionals

Exploit Details:

• The restore_mozzi_memories.sh script uses the tar command with the -C / flag, which allows extraction to the filesystem root.
• The lack of path validation enables attackers to overwrite critical files such as /etc/shadow or /var/www/index.php.

Detection and Response:

• Detection:

  • Monitor for unusual file upload activities and extraction processes.
  • Use file integrity monitoring tools to detect unauthorized changes to critical system files.

• Response:

  • Immediately isolate affected systems to prevent further compromise.
  • Restore affected files from backups.
  • Apply necessary patches and updates.
  • Conduct a thorough security audit to identify and mitigate similar vulnerabilities.

References:

• Exploit and Third Party Advisory

By addressing this vulnerability promptly and comprehensively, organizations can mitigate the risk of full system compromise and ensure the security and integrity of their telecommunication infrastructure.