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

Option	Description
-v, --verbose	Show detailed output
--json	Output results as JSON
--ci	Exit with code 1 if vulnerable (for CI/CD)
-t, --timeout	Connection timeout (default: 10s/10000ms)
-h, --help	Show help message

Exit Codes

Code	Meaning
0	Not vulnerable or scan completed
1	Vulnerable (when using --ci flag)
2	Scan error occurred

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

Property	Value
CVE ID	CVE-2025-52691
CVSS Score	10.0 (CRITICAL)
CVSS Vector	AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack Vector	Network
Authentication	None required
Impact	Complete system compromise

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.