SmarterMail CVE-2025-52691 Scanner

CVSS 10.0 RCE vulnerability in SmarterMail. Is your mail server vulnerable?

Fast, accurate scanner for CVE-2025-52691 - a critical unauthenticated arbitrary file upload vulnerability that enables remote code execution on SmarterMail servers.

About CVE-2025-52691

CVE-2025-52691 is a maximum severity (10.0 CVSS) vulnerability in SmarterMail that allows unauthenticated remote code execution through arbitrary file upload.

Key Facts:

• Affected: SmarterMail Build 9406 and earlier
• Attack Vector: Network (no authentication required)
• Impact: Complete server compromise (RCE)
• Patched: Build 9413+ (recommended: Build 9483)
• Discovery: Chua Meng Han, Centre for Strategic Infocomm Technologies (CSIT)

Prerequisites

Node.js Scanner:

• Node.js 12+ (no additional dependencies required)

Bash Scanner:

• Bash 3.2+
• curl

# Verify Node.js version
node --version  # Should be v12.0.0 or higher

# Verify curl (for Bash scanner)
curl --version

Quick Start

Node.js Scanner (Recommended - Cross-Platform)

# Clone and run
git clone https://github.com/nxgn-kd01/smartermail-cve-scanner.git
cd smartermail-cve-scanner
node scan.js https://mail.example.com

Bash Scanner (Unix/Linux/macOS)

# Clone and run
git clone https://github.com/nxgn-kd01/smartermail-cve-scanner.git
cd smartermail-cve-scanner
chmod +x scan.sh
./scan.sh https://mail.example.com

Direct Download

# Node.js version
curl -O https://raw.githubusercontent.com/nxgn-kd01/smartermail-cve-scanner/main/scan.js
node scan.js https://mail.example.com

# Bash version
curl -O https://raw.githubusercontent.com/nxgn-kd01/smartermail-cve-scanner/main/scan.sh
chmod +x scan.sh
./scan.sh https://mail.example.com

Usage

Scan a SmarterMail Server

# Using Node.js
node scan.js https://mail.example.com

# Using Bash
./scan.sh https://mail.example.com

Scan with Verbose Output

node scan.js https://mail.example.com --verbose
./scan.sh https://mail.example.com -v

JSON Output (for Automation)

node scan.js https://mail.example.com --json
./scan.sh https://mail.example.com --json

CI/CD Mode (Exit Code 1 if Vulnerable)

node scan.js https://mail.example.com --ci
./scan.sh https://mail.example.com --ci

Command Line Options

Exit Codes

Example Output

Vulnerable Server

+============================================================+
|  CVE-2025-52691 Scanner (SmarterMail RCE)               |
+============================================================+

Severity: CRITICAL (CVSS 10.0)
Type: Unauthenticated Arbitrary File Upload -> RCE

[INFO] Scanning target: https://mail.example.com

Scan Results:
  Target: https://mail.example.com
  SmarterMail detected
  Version: 100.0.9350
  Build: 9350

  STATUS: VULNERABLE
  Build 9350 is affected by CVE-2025-52691

  Remediation:
  $ Upgrade to SmarterMail Build 9483 or later
  $ Download: https://www.smartertools.com/smartermail/downloads

Patched Server

Scan Results:
  Target: https://mail.example.com
  SmarterMail detected
  Version: 100.0.9483
  Build: 9483

  STATUS: NOT VULNERABLE
  Build 9483 is patched

JSON Output

{
  "vulnerability": "CVE-2025-52691",
  "name": "SmarterMail RCE",
  "severity": "CRITICAL",
  "cvss": 10,
  "target": "https://mail.example.com",
  "smartermail_detected": true,
  "version": "100.0.9350",
  "build": 9350,
  "status": "vulnerable",
  "vulnerable": true,
  "vulnerable_max_build": 9406,
  "patched_min_build": 9413,
  "recommended_build": 9483
}

CI/CD Integration

GitHub Actions

name: SmarterMail Security Scan

on:
  schedule:
    - cron: '0 6 * * *'  # Daily at 6 AM
  workflow_dispatch:

jobs:
  scan:
    runs-on: ubuntu-latest
    steps:
      - name: Download Scanner
        run: |
          curl -O https://raw.githubusercontent.com/nxgn-kd01/smartermail-cve-scanner/main/scan.js

      - name: Scan Mail Server
        run: node scan.js ${{ secrets.MAIL_SERVER_URL }} --ci

GitLab CI

security-scan:
  stage: test
  image: node:18
  script:
    - curl -O https://raw.githubusercontent.com/nxgn-kd01/smartermail-cve-scanner/main/scan.js
    - node scan.js $MAIL_SERVER_URL --ci
  allow_failure: false

How It Works

The scanner:

1. Probes common SmarterMail endpoints to detect the application
2. Extracts version/build information from responses and headers
3. Compares the build number against known vulnerable versions
4. Reports vulnerability status with remediation guidance

Detection Methods

• Checks web interface login pages
• Parses version strings from HTML content
• Examines HTTP headers for version information
• Supports self-signed SSL certificates

Security Notes

• Zero dependencies: Uses only Node.js built-in modules (no npm packages) - eliminates supply chain risk
• SSL verification disabled: The scanner accepts self-signed certificates to scan internal/test servers. Only use on servers you own or have authorization to scan
• Read-only: The scanner only performs HTTP GET requests - it does not attempt to exploit the vulnerability

Vulnerability Details

Affected Versions

• SmarterMail Build 9406 and earlier

Patched Versions

• Build 9413+ (minimum patch)
• Build 9483+ (recommended)

Remediation

Step 1: Verify Vulnerability

node scan.js https://your-mail-server.com

Step 2: Update SmarterMail

Download the latest version from: https://www.smartertools.com/smartermail/downloads

Step 3: Verify Fix

node scan.js https://your-mail-server.com --ci

Temporary Mitigations

If immediate upgrade is not possible:

1. Restrict network access to the SmarterMail web interface
2. Use a Web Application Firewall (WAF) to filter malicious uploads
3. Monitor logs for suspicious file upload activity
4. Consider taking the web interface offline temporarily

References

• CSA Singapore Alert
• The Hacker News Coverage
• SmarterMail Release Notes
• SmarterMail Downloads

Contributing

Contributions are welcome! Please feel free to submit issues or pull requests.

License

MIT License - see LICENSE file for details

Legal Disclaimer

AUTHORIZED USE ONLY

This tool is intended for:

• Security professionals testing systems they own
• System administrators validating their own infrastructure
• Authorized penetration testers with written permission
• Educational and research purposes in controlled environments

You must have explicit authorization before scanning any system.

Unauthorized scanning of computer systems may violate laws including but not limited to:

• Computer Fraud and Abuse Act (CFAA) - United States
• Computer Misuse Act - United Kingdom
• Criminal Code Section 342.1 - Canada
• Similar cybercrime laws in other jurisdictions

The authors of this tool:

• Assume no liability for misuse or damage caused by this tool
• Do not condone or support unauthorized access to computer systems
• Provide this tool "as-is" without warranty of any kind

By using this tool, you acknowledge that you have the legal right to scan the target systems and accept full responsibility for your actions.

Stay safe and keep your mail servers updated!