AudioCodes Fax Server/Auto-Attendant IVR up to 2.6.23 Endpoint download.php path/filename missing authentication

Summaryinfo

A vulnerability, which was classified as critical, has been found in AudioCodes Fax Server and Auto-Attendant IVR up to 2.6.23. This issue affects some unknown processing of the file download.php of the component Endpoint. The manipulation of the argument path/filename leads to missing authentication. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is listed as CVE-2025-34331. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in AudioCodes Fax Server and Auto-Attendant IVR up to 2.6.23. It has been rated as critical. This issue affects an unknown functionality of the file download.php of the component Endpoint. The manipulation of the argument path/filename with an unknown input leads to a missing authentication vulnerability. Using CWE to declare the problem leads to CWE-306. The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources. Impacted is confidentiality. The summary by CVE is:

AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 contain an unauthenticated file read vulnerability via the download.php script. The endpoint exposes a file download mechanism that lacks access control, allowing remote, unauthenticated users to request files stored on the appliance based solely on attacker-supplied path and filename parameters. While limited to specific file extensions permitted by the application logic, sensitive backup archives can be retrieved, exposing internal databases and credential hashes. Successful exploitation may lead to disclosure of administrative password hashes and other sensitive configuration data.

The weakness was presented by Pierre Barre. It is possible to read the advisory at audiocodes.com. The identification of this vulnerability is CVE-2025-34331 since 04/15/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/12/2025).

By approaching the search of inurl:download.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.

Statistical analysis made it clear that VulDB provides the best quality 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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