Vulnerability Description
AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 expose an unauthenticated backup upload endpoint at AudioCodes_files/ajaxBackupUploadFile.php in the F2MAdmin web interface. The script derives a backup folder path from application configuration, creates the directory if it does not exist, and then moves an uploaded file to that location using the attacker-controlled filename, without any authentication, authorization, or file-type validation. On default Windows deployments where the backup directory resolves to the system drive, a remote attacker can upload web server or interpreter configuration files that cause a log file or other server-controlled resource to be treated as executable code. This allows subsequent HTTP requests to trigger arbitrary command execution under the web server account, which runs as NT AUTHORITY\\SYSTEM.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Audiocodes | Fax Server | <= 2.6.23 |
| Audiocodes | Interactive Voice Response | <= 2.6.23 |
Related Weaknesses (CWE)
References
- https://pierrekim.github.io/advisories/2025-audiocodes-fax-ivr.txtExploitThird Party Advisory
- https://pierrekim.github.io/blog/2025-11-20-audiocodes-fax-ivr-8-vulnerabilitiesExploitThird Party Advisory
- https://www.audiocodes.com/media/g1in2u2o/0548-product-notice-end-of-service-forProduct
- https://www.vulncheck.com/advisories/audiocodes-fax-ivr-appliance-unauthenticateThird Party Advisory
FAQ
What is CVE-2025-34329?
CVE-2025-34329 is a vulnerability with a CVSS score of 9.8 (CRITICAL). AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 expose an unauthenticated backup upload endpoint at AudioCodes_files/ajaxBackupUploadFile.php in the F2MAdmi...
How severe is CVE-2025-34329?
CVE-2025-34329 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2025-34329?
Check the references section above for vendor advisories and patch information. Affected products include: Audiocodes Fax Server, Audiocodes Interactive Voice Response.