CVE-2025-34331Public exploitNetwork attack vector

Unauthenticated backup disclosure via unchecked download parameters

Published Nov 19, 2025 · Updated Nov 20, 2025

Missing authentication in AudioCodes Fax Server and Auto Attendant IVR 2.6.23 and earlier allows remote attackers to read backup archives. The download.php endpoint uses attacker-supplied baseDir and f parameters to select an extension-allowed file without requiring a session. Network access to the appliance web service is sufficient to retrieve guessable backup ZIP files containing internal databases and administrative password hashes.

CVSS severity8.7
High
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authentication in AudioCodes Fax Server and Auto Attendant IVR 2.6.23 and earlier allows remote attackers to read backup archives. The download.php endpoint uses attacker-supplied baseDir and f parameters to select an extension-allowed file without requiring a session. Network access to the appliance web service is sufficient to retrieve guessable backup ZIP files containing internal databases and administrative password hashes.

The record

CVE
CVE-2025-34331
Published
Nov 19, 2025
Updated
Nov 20, 2025
Vendor
AudioCodes Ltd.
Product
Fax Server and Auto Attendant IVR
Classifications
CWE-306, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 19, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 20, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2.6.23

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

AudioCodes Ltd. · Fax Server and Auto Attendant IVRversion=0 <=2.6.23

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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