CVE-2025-34335
CVE-2025-34335 is a high-severity vulnerability in Audiocodes Fax Server with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v4: 8.7
- EPSS exploit prediction: 3% (84th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2025-198200
- Weakness: CWE-78
- Affected product: Audiocodes Fax Server
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2025-34335?
- 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.
- How severe is CVE-2025-34335?
- CVE-2025-34335 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2025-34335 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2025-34335?
- CVE-2025-34335 primarily affects Audiocodes Fax Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2025-34335?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2025-34335 have an EU (EUVD) identifier?
- Yes. CVE-2025-34335 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198200.
- When was CVE-2025-34335 published?
- CVE-2025-34335 was published on 2025-11-19 and last updated on 2026-06-17.
References
- https://pierrekim.github.io/advisories/2025-audiocodes-fax-ivr.txt
- https://pierrekim.github.io/blog/2025-11-20-audiocodes-fax-ivr-8-vulnerabilities.html
- https://www.audiocodes.com/media/g1in2u2o/0548-product-notice-end-of-service-for-audiocodes-auto-attendant-ivr-solution.pdf
- https://www.vulncheck.com/advisories/audiocodes-fax-ivr-appliance-authenticated-command-injection-via-activatelicense
Affected products (2)
- cpe:2.3:a:audiocodes:fax_server:*:*:*:*:*:*:*:*
- cpe:2.3:a:audiocodes:interactive_voice_response:*:*:*:*:*:*:*:*
More vulnerabilities in Audiocodes Fax Server
- CVE-2025-34329 — Critical (CVSS 9.8): AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 expose an unauthenticated…
- CVE-2025-34328 — Critical (CVSS 9.8): AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 include a web…
- CVE-2025-34334 — High (CVSS 8.8): AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 are vulnerable to an…
- CVE-2025-34333 — High (CVSS 7.8): AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 configure the web document…
- CVE-2025-34332 — High (CVSS 7.8): AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 include a web…
- CVE-2025-34331 — High (CVSS 7.5): AudioCodes Fax Server and Auto-Attendant IVR appliances versions up to and including 2.6.23 contain an unauthenticated…
All CVEs affecting Audiocodes Fax Server →
Other CWE-78 (OS Command Injection) vulnerabilities
- CVE-2026-56004 — Critical (CVSS 10.0): A shellcode injection in the mercurial handler of the obs tar_scm source service before version 0.12.4 could be used by…
- CVE-2026-56415 — Critical (CVSS 10.0): Storage Concentrator (SC & SCVM) contains a command injection vulnerability within the debug.pl script that is…
- CVE-2026-56413 — Critical (CVSS 10.0): Storage Concentrator (SC & SCVM) contains a command injection vulnerability in the ms_service.pl service, which listens…
- CVE-2026-49869 — Critical (CVSS 10.0): Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, AuthenticationFilter in…
- CVE-2026-49261 — Critical (CVSS 10.0): MariaDB server is a community developed fork of MySQL server. Versions 10.6.1 through 10.6.26, 10.11.1 through…
- CVE-2026-10520 — Critical (CVSS 10.0): An OS Command Injection vulnerability in Ivanti Sentry before the R10.5.2, R10.6.2 and R10.7.1 versions allows a…