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Weak Default Password Allows Unauthenticated Access in Endpoint Module REST API

Moderate
chrsmj published GHSA-426v-c5p7-cp29 Dec 9, 2025

Package

endpoint (FreePBX 16)

Affected versions

16

Patched versions

16.0.96
endpoint (FreePBX 17)
17
17.0.10

Description

Summary

A password is needed to access the endpoint. By default, this is a 6 digit numeric value which can be brute forced. (This is the app_password parameter).

Depending on local configuration, this password could be the extension, voicemail, user manager, DPMA or EPM phone admin password.

Mitigations

  • Update to the latest fixed version of the endpoint module, which sets new installs up with 16 digit randomized default passwords for phone admin, user and DPMA, plus adds Dashboard warnings for lesser passwords.
  • Protect your Phone Apps from suspicious users.
  • Isolate telephony network from the public internet e.g. OpenVPN, VLANs, etc.
  • Remove users and extensions that should not have access.
  • Review password policies, e.g., length, upper-case, lower-case, etc., in Admin -> User Management -> Settings -> Authentication Settings (and Password Management.)
  • Change passwords to longer randomized strings, e.g., 16 digits that you share with users in four blocks of four digits each might be okay for a voicemail password in your environment.
  • Change Phone Admin Password (under Endpoint Manager -> Global Settings).
  • Change DPMA Global PIN (under Endpoint Manager -> Global Settings -> DPMA Management).
  • Utilize User Manager authentication (under Phone Apps -> Endpoint Manager -> User Manager authentication). This option is not available on phones using DPMA.
  • Consider hardware firewall for your FreePBX RESTful Phone Apps ports (ports listed under System Admin -> Port Management).
  • Check FreePBX Responsive Firewall is active as this can limit access to Phone Apps to the IPs of SIP phones which already registered successfully (see previous blog post for more information: https://www.freepbx.org/freepbx-security-issue-sec-2023-001/ as well as the previous issue linked therein that the current fix is very closely related to: https://sangomakb.atlassian.net/wiki/spaces/FP/pages/13008945/2023-08-28+SECURITY+Potential+Rest+Phone+Apps+Authentication+issue)
  • Require tokens for all endpoints (under Advanced Settings -> Phone Apps -> Enable Token Based Security). TEST IT FIRST AND BE READY TO REBOOT ALL YOUR PHONES SHOULD YOU DECIDE TO ACTIVATE TOKENS.

Scoring

CVSS 4.0 Base vector string: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
CVSS 4.0 more complete vector string: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/MUI:P/AU:Y/R:U/V:D/RE:L/U:Green
Current CVSS v4.0 Base score is 6.9 (Medium)
Current CVSS v4.0 more complete score is 2.1 (Low)
Alternative CVSS v4.1 score is 2.1 (Low)

See details on scoring on the FreePBX blog at https://www.freepbx.org/watch-what-we-do-with-security-fixes-%f0%9f%91%80/

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v4 base metrics

Exploitability Metrics
Attack Vector Network
Attack Complexity Low
Attack Requirements None
Privileges Required None
User interaction None
Vulnerable System Impact Metrics
Confidentiality Low
Integrity Low
Availability None
Subsequent System Impact Metrics
Confidentiality None
Integrity None
Availability None

CVSS v4 base metrics

Exploitability Metrics
Attack Vector: This metric reflects the context by which vulnerability exploitation is possible. This metric value (and consequently the resulting severity) will be larger the more remote (logically, and physically) an attacker can be in order to exploit the vulnerable system. The assumption is that the number of potential attackers for a vulnerability that could be exploited from across a network is larger than the number of potential attackers that could exploit a vulnerability requiring physical access to a device, and therefore warrants a greater severity.
Attack Complexity: This metric captures measurable actions that must be taken by the attacker to actively evade or circumvent existing built-in security-enhancing conditions in order to obtain a working exploit. These are conditions whose primary purpose is to increase security and/or increase exploit engineering complexity. A vulnerability exploitable without a target-specific variable has a lower complexity than a vulnerability that would require non-trivial customization. This metric is meant to capture security mechanisms utilized by the vulnerable system.
Attack Requirements: This metric captures the prerequisite deployment and execution conditions or variables of the vulnerable system that enable the attack. These differ from security-enhancing techniques/technologies (ref Attack Complexity) as the primary purpose of these conditions is not to explicitly mitigate attacks, but rather, emerge naturally as a consequence of the deployment and execution of the vulnerable system.
Privileges Required: This metric describes the level of privileges an attacker must possess prior to successfully exploiting the vulnerability. The method by which the attacker obtains privileged credentials prior to the attack (e.g., free trial accounts), is outside the scope of this metric. Generally, self-service provisioned accounts do not constitute a privilege requirement if the attacker can grant themselves privileges as part of the attack.
User interaction: This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable system. This metric determines whether the vulnerability can be exploited solely at the will of the attacker, or whether a separate user (or user-initiated process) must participate in some manner.
Vulnerable System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the VULNERABLE SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the VULNERABLE SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the VULNERABLE SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
Subsequent System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the SUBSEQUENT SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the SUBSEQUENT SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the SUBSEQUENT SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

CVE ID

CVE-2025-67513

Weaknesses

Weak Password Requirements

The product does not require that users should have strong passwords, which makes it easier for attackers to compromise user accounts. Learn more on MITRE.

Credits