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CVE-2026-73663: Sangoma Freepbx: Authentication bypass

CVE-2026-73663 is rated critical with a CVSS v3.1 base score of 9.8 and affects Sangoma Freepbx. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

FreePBX is an open source IP PBX. From 16.0.0 until 16.0.11 and 17.0.4, the FreePBX missedcall module places the inbound Caller ID name from crafted SIP From headers into the missedcalllog INSERT in agi-bin/missedcallnotify.php without escaping or bound parameters. An unauthenticated caller can inject SQL when a monitored extension goes unanswered, corrupting the database and modifying FreePBX administrator accounts to obtain unauthorized remote access. This issue is fixed in versions 16.0.11 and 17.0.4.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-89: Improper Neutralization of Special Elements used in an SQL Command

The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.

Affected products

  • Sangoma Freepbx: from 16.0 before 16.0.11; from 17.0 before 17.0.4

References