Port 1590: SWMFS — Where Infrastructure Lives in Data

Port 1590 carries something most people never see but depend on daily: the GE Smallworld Master Filesystem (SWMFS), a specialized database system that utilities, telecommunications companies, and governments use to manage their physical infrastructure networks.

What Runs on Port 1590

The officially registered service name is gemini-lm, but the actual application is the Smallworld Master Filesystem (SWMFS)—the datastore component of GE Vernova's Smallworld GIS platform.¹

When an electric utility needs to know which transformer serves which neighborhood, or a telecom company needs to route fiber through a city, the data lives in Smallworld. And Smallworld's data lives on port 1590.

How SWMFS Works

SWMFS is composed of two parts: a simple, highly scalable data block server (the SWMFS server itself) and an intelligent client API.² The architecture is designed specifically for storing and analyzing complex spatial and topological data—the kind of information that describes how physical networks actually connect in the real world.

The server listens on TCP port 1590, waiting for client connections that need to read or write infrastructure data. Every query about "what's connected to what" or "where does this cable run" flows through this port.

The History

Smallworld was founded in Cambridge, England, in 1989, creating specialized GIS software optimized for network management—utilities, telecoms, anyone managing physical infrastructure spread across geography.³ General Electric acquired the company in 2010, and it's now part of GE Vernova's digital portfolio.

Port 1590 has been carrying this traffic since the 1990s. The protocol is old enough that it predates modern security practices, which has consequences we'll discuss below.

Why This Port Matters

You've probably never heard of Smallworld, but you depend on it. Electric utilities use it to manage power grids. Water companies use it to track pipes. Telecom providers use it to plan fiber deployments. Cities use it for planning and emergency response.

When the power goes out and the utility company knows exactly which transformer failed and which houses are affected—that knowledge came from Smallworld. When emergency services need to know where water mains are located before digging—they're querying Smallworld. That data flows through port 1590.

Security Considerations

In November 2025, GE Vernova published two critical security advisories about SWMFS:⁴⁵

CVE-2025-3222 (CVSS 9.3 - Critical): An improper authentication vulnerability that allows authentication abuse. Network-based attack, requires no authentication, affects Smallworld 5.3.3 and prior for Linux, 5.3.4 for Windows.

CVE-2025-7719 (CVSS 5.3 - Medium): A path traversal vulnerability allowing arbitrary file operations, affecting Smallworld 5.3.5 and previous versions.

These aren't theoretical risks. SWMFS manages data about critical infrastructure—power grids, water systems, telecom networks. An attacker who compromises SWMFS doesn't just get data. They get maps of how infrastructure works, which could be used to plan physical attacks or disruptions.

If you're running Smallworld:

• Ensure you're on the latest patched version
• Never expose port 1590 directly to the Internet
• Use VPNs or other secure channels for remote access
• Monitor connections to this port for unusual activity
• Follow GE Vernova's security advisories closely

Checking What's Listening

To see if something is listening on port 1590 on your system:

# Linux/Mac
sudo lsof -i :1590
sudo netstat -tlnp | grep 1590

# Windows
netstat -ano | findstr :1590

If you see something listening and you're not running Smallworld, investigate immediately.

Related Ports

Smallworld installations may use additional ports:

• Port 30000: FME (Feature Manipulation Engine) default port for connecting to Smallworld services⁶
• Various ephemeral ports for client connections

The Persistent Reality

Port 1590 has been carrying infrastructure data for over thirty years. The protocol is showing its age—hence the recent CVEs—but the data it carries is more critical than ever. As cities grow smarter and grids grow more complex, the databases mapping physical infrastructure become increasingly important.

The maps of our infrastructure live in data. And much of that data, for better or worse, flows through port 1590.