CVE-2025-34329: AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 expose an unauthenticated backup upload endpoint at…

PriorityP273critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

1.02%

59.0th percentile

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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
audiocodes	fax_server	<= 2.6.23	—
audiocodes	interactive_voice_response	<= 2.6.23	—
audiocodes_limited	audiocodes_fax_ivr_appliance	<= 2.6.23	—

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv4.09.3CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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