CVE-2026-44237 PUBLISHED

FreePBX: Authenticated Access can lead to Subsequent OAuth2 Authentication Bypass in API Module

Assigner: GitHub_M
Reserved: 05.05.2026 Published: 29.05.2026 Updated: 29.05.2026

FreePBX is an open source IP PBX. Prior to 17.0.8, the FreePBX api module's OAuth2 implementation does not sufficiently validate client credentials during token issuance. Knowledge of a valid client_id is required. The validateClient() method in ClientRepository.php unconditionally returns true, allowing any party with knowledge of a valid client_id to obtain OAuth2 access tokens without providing the correct client_secret. This vulnerability is fixed in 17.0.8.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CVSS Score: 7.6

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

CVSS 4.0

Product Status

Vendor	FreePBX
Product	security-reporting
Versions	Version < 17.0.8 is affected

References

https://github.com/FreePBX/security-reporting/security/advisories/GHSA-vgjf-4h63-8vcc

Problem Types

CWE-1390: Weak Authentication CWE