Critical 9.3Published Nov 19, 2025

CVE-2025-34329AudioCodes Fax/IVR Appliance <= 2.6.23 Unauthenticated Backup Upload RCE via ajaxBackupUploadFile.php

Updated under an hour ago (Oct 27, 2026, 3:30 AM ET)

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It affects AudioCodes Limited AudioCodes Fax/IVR Appliance and 2 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for AudioCodes Limited AudioCodes Fax/IVR Appliance

Exploited in the last 30 days

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: 9.3 CRITICAL (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-434
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Analyzed
Record last updated: Nov 20, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

AudioCodes Limited AudioCodes Fax/IVR Appliance audiocodes:fax_ivr_appliance (from the name)	through 2.6.23	CNA record
audiocodes fax_server audiocodes:fax_server	through 2.6.23	NVD
audiocodes interactive_voice_response audiocodes:interactive_voice_response	through 2.6.23	NVD

References

References

https://www.audiocodes.com/media/g1in2u2o/0548-product-notice-end-of-service-for-audiocodes-auto-attendant-ivr-solution.pdf	vendor-advisory, patch, mitigation, product
https://pierrekim.github.io/blog/2025-11-20-audiocodes-fax-ivr-8-vulnerabilities.html	technical-description, exploit, third-party-advisory
https://pierrekim.github.io/advisories/2025-audiocodes-fax-ivr.txt	technical-description, exploit, third-party-advisory
https://www.vulncheck.com/advisories/audiocodes-fax-ivr-appliance-unauthenticated-backup-upload-rce-via-ajaxbackupuploadfile	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.