CVE-2019-19006: Sangoma FreePBX Improper Authentication Vulnerability

Sangoma FreePBX contains an improper authentication vulnerability that potentially allows unauthorized users to bypass password authentication and access services provided by the FreePBX admin. This matters because administrative access to a PBX system can expose call routing, user accounts, and connected telephony resources.

How it works

The weakness is classified under CWE-287, improper authentication. An attacker can abuse the flaw to reach administrative services without supplying valid credentials that the application would normally require.

Am I affected? How to find it in your systems

Sangoma FreePBX typically runs on Linux-based servers that provide VoIP and PBX functions. Inventory instances by locating FreePBX installations through package managers, web server configurations, or network scans for known administrative interfaces. Check the exact versions and configurations deployed in your environment against the vendor advisory, as only the advisory lists the affected releases.

• Review web server logs and authentication logs for repeated or anomalous requests to administrative endpoints that do not produce expected credential failures.
• Correlate any unexpected administrative sessions with source IP addresses that lack prior authorization.

How to remediate

Apply the vendor update referenced in the advisory as the primary step. After patching, review authentication settings for the administrative interface and enforce any additional controls recommended for this class of weakness, such as restricting direct network access to management ports.

If you can't patch immediately

Apply mitigations per the vendor instructions. For cloud-hosted instances, follow applicable BOD 22-01 guidance. Where mitigations are unavailable, discontinue use of the affected product. Additional compensating steps include network segmentation that limits administrative interface exposure and monitoring for unexpected access patterns until the update can be applied.

If your data may have been exposed

Vulnerabilities that permit unauthorized administrative access can lead to data exposure when exploited. You can run a free exposure scan of your email addresses against known breach data to check for prior incidents.