CVE-2025-57819
📋 TL;DR
CVE-2025-57819 is a critical vulnerability in FreePBX that allows unauthenticated attackers to bypass authentication, gain administrator access, manipulate databases, and execute arbitrary code. It affects FreePBX versions 15, 16, and 17 before specific patched versions. Organizations using vulnerable FreePBX installations are at immediate risk.
💻 Affected Systems
- FreePBX
📦 What is this software?
Freepbx by Sangoma
Freepbx by Sangoma
Freepbx by Sangoma
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise: attacker gains full administrative control, executes arbitrary code, steals sensitive data, and uses the system as a foothold for lateral movement.
Likely Case
Unauthenticated attacker gains administrator access, manipulates PBX configuration, installs backdoors, and potentially executes remote code.
If Mitigated
With proper network segmentation and access controls, impact limited to PBX system compromise without lateral movement to other systems.
🎯 Exploit Status
Exploit code is publicly available and actively used in attacks. CISA has added this to their Known Exploited Vulnerabilities catalog.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 15.0.66, 16.0.89, 17.0.3
Vendor Advisory: https://github.com/FreePBX/security-reporting/security/advisories/GHSA-m42g-xg4c-5f3h
Restart Required: Yes
Instructions:
1. Backup your FreePBX configuration. 2. Update FreePBX via the web interface (Admin → Module Admin → Check Online → Upgrade All). 3. Alternatively, use CLI: 'fwconsole ma upgradeall'. 4. Restart FreePBX services: 'fwconsole restart'.
🔧 Temporary Workarounds
Restrict Administrator Access
linuxLimit access to FreePBX administrator interface to trusted IP addresses only
iptables -A INPUT -p tcp --dport 80 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Disable Web Interface Temporarily
linuxTemporarily disable FreePBX web interface while patching
systemctl stop httpd
systemctl stop nginx
🧯 If You Can't Patch
- Immediately restrict network access to FreePBX web interface using firewall rules
- Implement network segmentation to isolate FreePBX from critical systems
🔍 How to Verify
Check if Vulnerable:
Check FreePBX version via web interface (Admin → System Admin → About) or CLI: 'fwconsole ma list | grep framework'Check Version:
fwconsole ma list | grep frameworkVerify Fix Applied:
Verify version is 15.0.66+, 16.0.89+, or 17.0.3+. Test authentication bypass attempts fail.📡 Detection & Monitoring
Log Indicators:
- Unauthenticated access to administrator endpoints
- SQL injection attempts in web logs
- Unusual database modification events
- Failed authentication followed by successful admin access
Network Indicators:
- Unusual outbound connections from FreePBX server
- Traffic to known malicious IPs
- Exploit kit signatures in web traffic
SIEM Query:
source="freepbx_access.log" AND (uri="/admin/*" OR uri="/rest/*") AND status=200 AND (user="-" OR auth="-")🔗 References
- https://community.freepbx.org/t/security-advisory-please-lock-down-your-administrator-access/107203
- https://github.com/FreePBX/security-reporting/security/advisories/GHSA-m42g-xg4c-5f3h
- https://github.com/watchtowrlabs/watchTowr-vs-FreePBX-CVE-2025-57819
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-57819
