CVE-2023-1307
📋 TL;DR
CVE-2023-1307 is an authentication bypass vulnerability in the Froxlor server management panel that allows attackers to gain unauthorized administrative access without valid credentials. This affects all Froxlor installations prior to version 2.0.13. The vulnerability stems from improper authentication logic that can be exploited to bypass login requirements.
💻 Affected Systems
- froxlor/froxlor
📦 What is this software?
Froxlor by Froxlor
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the Froxlor instance allowing attacker to create/delete domains, manage customer accounts, access sensitive server configuration data, and potentially pivot to underlying server infrastructure.
Likely Case
Unauthorized administrative access leading to data theft, service disruption, and privilege escalation within the Froxlor environment.
If Mitigated
Limited impact if proper network segmentation and access controls prevent external access to Froxlor interface.
🎯 Exploit Status
The vulnerability is simple to exploit with publicly available details. The authentication bypass can be triggered through crafted requests to the login mechanism.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.0.13
Vendor Advisory: https://github.com/froxlor/froxlor/commit/6777fbf229200f4fd566022e186548391219ab23
Restart Required: No
Instructions:
1. Backup your current Froxlor installation and database. 2. Download Froxlor 2.0.13 or newer from the official repository. 3. Replace the existing installation files with the patched version. 4. Clear any PHP opcache if enabled. 5. Verify the update was successful by checking the version in the Froxlor interface.
🔧 Temporary Workarounds
Restrict Network Access
linuxLimit access to Froxlor panel to trusted IP addresses only using firewall rules.
# Example for iptables: 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
Web Server Access Control
allImplement IP-based restrictions at the web server level (Apache/Nginx).
# Apache example: Require ip 192.168.1.0/24
# Nginx example: allow 192.168.1.0/24; deny all;
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to isolate Froxlor from untrusted networks
- Enable multi-factor authentication if supported, though this may not fully mitigate the bypass vulnerability
🔍 How to Verify
Check if Vulnerable:
Check Froxlor version in the admin panel or by examining the lib/classes/froxlor/Froxlor.php file for version string. Versions below 2.0.13 are vulnerable.Check Version:
grep -r "\$version" /path/to/froxlor/lib/classes/froxlor/Froxlor.php | head -1Verify Fix Applied:
After updating, verify the version shows 2.0.13 or higher in the Froxlor interface. Test authentication with valid and invalid credentials to ensure proper validation.📡 Detection & Monitoring
Log Indicators:
- Multiple failed login attempts followed by successful login from same IP
- Successful admin logins from unusual IP addresses
- Authentication bypass patterns in web server access logs
Network Indicators:
- Unusual HTTP POST requests to login endpoints with crafted parameters
- Traffic to Froxlor admin interface from unexpected sources
SIEM Query:
source="froxlor_access.log" (POST /admin/login OR POST /index.php) AND (status=200 OR status=302) AND NOT (user_agent="browser_signature")