Auth bypass in Audiocodes Fax Server

CVE-2025-34331

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.

Vulnerability class: Broken Authentication

EPSS: 0.005 (41.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-34331?
CVE-2025-34331 is a high-severity vulnerability in Audiocodes Fax Server, classified under Missing Authentication for Critical Function. CVSS score: 7.5/10. Published 2025-11-19.
How severe is CVE-2025-34331?
High severity. CVSS v3 base score is 7.5 out of 10.