Port 9512 – ALTERNATE (Alternate Service)

Service:

alternate

Protocol:

TCP

Port:

9512

Used for:

Alternative service port

Why It’s Open

Port 9512 is primarily used by FirstClass collaboration software and Sphinx Search daemon. FirstClass is a client-server groupware platform providing email, messaging, and collaborative services, while Sphinx is an open-source full-text search engine commonly used for website search functionality.

Common Risks

  • Outdated software vulnerabilities
    Legacy FirstClass installations often contain unpatched security issues.
  • Weak authentication mechanisms
    Both services may implement inadequate credential security.
  • SQL injection in search queries
    Sphinx search daemon may process malicious queries leading to data exposure.
  • Information leakage
    Collaboration platforms potentially expose sensitive communications and files.
  • Unauthorized index access
    Improperly secured search indices may reveal data without authentication.

Enumeration & Testing

Service Detection:

Terminal window
nmap -sV -p 9512

FirstClass Service Testing:

Terminal window
curl http://:9512 telnet 9512

Sphinx Search Testing:

Terminal window
echo "SELECT * FROM index_name" | nc 9512

What to Look For

CheckpointWhat it means
Service versionIdentify software version and patch level
AuthenticationCheck for default or weak credentials
SSL/TLS configVerify encryption settings if applicable
Access controlsTest for proper authorization mechanisms

Mitigation

  • Keep software updated
    Apply latest security patches
  • Strong authentication
    Use complex passwords and 2FA
  • Access restrictions
    Limit service to trusted networks
  • Monitor activity
    Log and review service usage
  • Disable if unused
    Remove unnecessary services

TL;DR

  • Port 9512 = FirstClass/Sphinx search with collaboration and search daemon vulnerabilities
  • Protocol: TCP
  • Used for: FirstClass collaboration server and Sphinx search daemon
  • Security focus: Legacy collaboration software and search engine security

Known CVEs and Exploits

  • CVE-2005-0468 - FirstClass Internet Services buffer overflow vulnerability allowing remote code execution.
  • CVE-2011-0484 - Sphinx Search SQL injection vulnerability in search queries.
  • CVE-2010-4260 - FirstClass information disclosure vulnerability exposing user data.