CVE-2026-73664

Received Received - Intake

Authenticated SSH Key Injection in FreePBX Admin Backup

Publication date: 2026-08-13

Last updated on: 2026-08-13

Assigner: GitHub, Inc.

Description

FreePBX is an open source IP PBX. From 17.0.5.34 until 17.0.11, the publicKeySave AJAX endpoint in Backup.class.php accepts an authenticated administrator's SSH public key and appends it to /home/asterisk/.ssh/authorized_keys for the asterisk system user without reliably enforcing backup-only command and source restrictions. The key grants persistent shell access that can execute arbitrary commands, access FreePBX and call data, modify system files, and disrupt services. This issue is fixed in version 17.0.11.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-13

Last Modified

2026-08-13

Generated

2026-08-14

AI Q&A

2026-08-14

EPSS Evaluated

N/A

NVD

CVE-2026-73664

Affected Vendors & Products

Vendor	Product	Version / Range
freepbx	freepbx	to 17.0.11 (inc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-732	The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.
CWE-269	The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
CWE-284	The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

Attack-Flow Graph

Executive Summary

This vulnerability in FreePBX allows an authenticated administrator to add an SSH public key to the system user's authorized_keys file without proper restrictions. This grants persistent shell access, enabling arbitrary command execution, data access, and service disruption.

Detection Guidance

Check if unauthorized SSH keys exist in /home/asterisk/.ssh/authorized_keys. Inspect Backup.class.php for the publicKeySave endpoint handling SSH key storage. Review FreePBX admin logs for unexpected SSH key additions.

Impact Analysis

An attacker with access could execute commands, steal call data, modify system files, or disrupt services. This requires authentication but bypasses intended backup-only restrictions.

Mitigation Strategies

Upgrade FreePBX to version 17.0.11 or later. Remove any unauthorized SSH keys from /home/asterisk/.ssh/authorized_keys. Restrict access to the Backup.class.php publicKeySave endpoint. Monitor system logs for suspicious activity.

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