FreePBX up to 16.0.43/17.0.22 improper authentication

Summaryinfo

A vulnerability, which was classified as critical, was found in FreePBX up to 16.0.43/17.0.22. Affected is an unknown function. Executing a manipulation can lead to improper authentication. The identification of this vulnerability is CVE-2025-66039. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in FreePBX up to 16.0.43/17.0.22. It has been declared as very critical. This vulnerability affects some unknown functionality. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

FreePBX Endpoint Manager is a module for managing telephony endpoints in FreePBX systems. Versions are vulnerable to authentication bypass when the authentication type is set to "webserver." When providing an Authorization header with an arbitrary value, a session is associated with the target user regardless of valid credentials. This issue is fixed in versions 16.0.44 and 17.0.23.

The advisory is available at github.com. This vulnerability was named CVE-2025-66039 since 11/21/2025. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 02/02/2026).

Upgrading to version 16.0.44 or 17.0.23 eliminates this vulnerability. Applying the patch 04224253156543cd9932b90458660b2f19fc0e35 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

• FreePBX

Version

• 16.0.0
• 16.0.1
• 16.0.2
• 16.0.3
• 16.0.4
• 16.0.5
• 16.0.6
• 16.0.7
• 16.0.8
• 16.0.9
• 16.0.10
• 16.0.11
• 16.0.12
• 16.0.13
• 16.0.14
• 16.0.15
• 16.0.16
• 16.0.17
• 16.0.18
• 16.0.19
• 16.0.20
• 16.0.21
• 16.0.22
• 16.0.23
• 16.0.24
• 16.0.25
• 16.0.26
• 16.0.27
• 16.0.28
• 16.0.29
• 16.0.30
• 16.0.31
• 16.0.32
• 16.0.33
• 16.0.34
• 16.0.35
• 16.0.36
• 16.0.37
• 16.0.38
• 16.0.39
• 16.0.40
• 16.0.41
• 16.0.42
• 16.0.43
• 17.0.0
• 17.0.1
• 17.0.2
• 17.0.3
• 17.0.4
• 17.0.5
• 17.0.6
• 17.0.7
• 17.0.8
• 17.0.9
• 17.0.10
• 17.0.11
• 17.0.12
• 17.0.13
• 17.0.14
• 17.0.15
• 17.0.16
• 17.0.17
• 17.0.18
• 17.0.19
• 17.0.20
• 17.0.21
• 17.0.22

License

• open-source

CPE 2.3info

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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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