CVE-2025-34334
AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 are vulnerable to an authenticated command injection in the fax test functionality implemented by AudioCodes_files/TestFax.php.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (3.44%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 are vulnerable to an authenticated command injection in the fax test functionality implemented by AudioCodes_files/TestFax.php. When a fax "send" test is requested, the application builds a faxsender command line using attacker-supplied parameters and passes it to GlobalUtils::RunBatchFile without proper validation or shell-argument sanitization. The resulting batch file is written into a temporary run directory and then executed via a backend service that runs as NT AUTHORITY\\SYSTEM. An authenticated attacker with access to the fax test interface can craft parameter values that inject additional shell commands into the generated batch file, leading to arbitrary command execution with SYSTEM privileges. In addition, because the generated batch files reside in a location with overly permissive file system permissions, a local low-privilege user on the server can modify pending batch files to achieve the same elevation.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/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/M
- EPSS
- 3.44% probability · 88th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-78
- Affected
- audiocodes/fax server · audiocodes/interactive voice response
- Source
- disclosure@vulncheck.com
References
- https://pierrekim.github.io/advisories/2025-audiocodes-fax-ivr.txtExploit, Third Party Advisory
- https://pierrekim.github.io/blog/2025-11-20-audiocodes-fax-ivr-8-vulnerabilities.htmlExploit, Third Party Advisory
- https://www.audiocodes.com/media/g1in2u2o/0548-product-notice-end-of-service-for-audiocodes-auto-attendant-ivr-solution.pdfProduct
- https://www.vulncheck.com/advisories/audiocodes-fax-ivr-appliance-authenticated-command-injection-via-testfax-and-lpeThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.