AudioCodes Fax Server/Auto-Attendant IVR up to 2.6.23 Web Interface ajaxBackupUploadFile.php unrestricted upload

Summaryinfo

A vulnerability, which was classified as critical, was found in AudioCodes Fax Server and Auto-Attendant IVR up to 2.6.23. Impacted is an unknown function of the file AudioCodes_files/ajaxBackupUploadFile.php of the component Web Interface. The manipulation results in unrestricted upload. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is cataloged as CVE-2025-34329. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as very critical has been found in AudioCodes Fax Server and Auto-Attendant IVR up to 2.6.23. Affected is some unknown functionality of the file AudioCodes_files/ajaxBackupUploadFile.php of the component Web Interface. The manipulation with an unknown input leads to a unrestricted upload vulnerability. CWE is classifying the issue as CWE-434. The product allows the attacker to upload or transfer files of dangerous types that can be automatically processed within the product's environment. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was shared by Pierre Barre. The advisory is shared for download at audiocodes.com. This vulnerability is traded as CVE-2025-34329 since 04/15/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 12/12/2025). The MITRE ATT&CK project declares the attack technique as T1608.002.

By approaching the search of inurl:AudioCodes_files/ajaxBackupUploadFile.php it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• AudioCodes

Name

• Auto-Attendant IVR
• Fax Server

Version

• 2.6.0
• 2.6.1
• 2.6.2
• 2.6.3
• 2.6.4
• 2.6.5
• 2.6.6
• 2.6.7
• 2.6.8
• 2.6.9
• 2.6.10
• 2.6.11
• 2.6.12
• 2.6.13
• 2.6.14
• 2.6.15
• 2.6.16
• 2.6.17
• 2.6.18
• 2.6.19
• 2.6.20
• 2.6.21
• 2.6.22
• 2.6.23

Support

• end of life

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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