CVE-2025-34335: AudioCodes Fax/IVR Appliance · OS Command Injection
Affects AudioCodes Fax/IVR ApplianceSource CVE Database V5
Not known to be exploited · CVSS 8.7 High.
Data as of 26 Oct 2026, 15:59 UTC
- EPSS
- 2.8% chance of exploitation in 30 days – higher than 86% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 19 Nov 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| AudioCodes Limited AudioCodes Fax/IVR Appliance | Affected
| Fixed in– |
AI-suggested
- Immediately restrict access to the license upload interface to trusted administrators only, using network segmentation and strong authentication mechanisms such as multi-factor authentication (MFA).
- Monitor and audit all license upload activities and system logs for suspicious filename patterns or command execution anomalies.
- Implement strict input validation and sanitization on the filename extension field if possible via configuration or custom scripting to block shell metacharacters.
- Disable or isolate the license activation functionality temporarily if feasible until a vendor patch is available.
- Coordinate with AudioCodes for timely patch deployment once released; maintain close vendor communication for updates.
- Employ endpoint detection and response (EDR) tools to detect unusual process executions or privilege escalations on affected appliances.
- Conduct regular credential audits and enforce least privilege principles to reduce the risk of credential compromise enabling exploitation.
- Consider network-level protections such as Web Application Firewalls (WAF) or Intrusion Prevention Systems (IPS) with custom rules targeting suspicious upload requests.
Description
AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 expose an authenticated command injection vulnerability in the license activation workflow handled by AudioCodes_files/ActivateLicense.php. When a license file is uploaded, the application derives a new filename by combining a generated base name with the attacker-controlled extension portion of the original upload name, then constructs a command line for fax_server_lic_cmdline.exe that includes this path. The extension value is incorporated into the command string without input validation, escaping, or proper argument quotation before being passed to exec(). An authenticated user with access to the license upload interface can supply a specially crafted filename whose extension injects additional shell metacharacters, causing arbitrary commands to be executed as NT AUTHORITY\\SYSTEM.
References
- audiocodes.com/media/g1in2u2o/0548-product-notice-end-of-service-for-audiocodes-auto-attendant-ivr-solution.pdf (opens in a new tab)
- pierrekim.github.io/blog/2025-11-20-audiocodes-fax-ivr-8-vulnerabilities.html (opens in a new tab)
- pierrekim.github.io/advisories/2025-audiocodes-fax-ivr.txt (opens in a new tab)
- vulncheck.com/advisories/audiocodes-fax-ivr-appliance-authenticated-command-injection-via-activatelicense (opens in a new tab)