Can My Local AI Be Reached from the Outside? — I Checked Whether the PC Running Ollama Is Safe

September 9, 2026

Once you have local LLMs running on your own computer, it is natural to want to reach them from a phone or another computer elsewhere in the house. This is easy to set up — changing a setting is all it takes.

But a published investigation found local LLMs with that setting turned on, visible from anywhere in the world. Has my own setup ended up reachable from the outside?

This is current as of September 2026.

What I Looked Into and Checked

• What Ollama, the software that runs local LLMs, accepts connections from by default (published documentation)
• A 2026 report on what happens when it is reachable from outside (an investigation)
• The current state of the two machines I run it on myself (measured)

By Default, Ollama Only Accepts Connections from Its Own Machine

Left as installed, Ollama only accepts connections from inside its own computer (127.0.0.1, commonly called localhost). Nothing from another machine on the same home Wi-Fi gets through.

The setting that changes this range is OLLAMA_HOST. Set it to 0.0.0.0 and the machine accepts connections on every interface it has. Searching for how to reach it from another machine at home, this is the first method that comes up.

The problem is that Ollama has no mechanism to verify who is connecting. Whatever request arrives gets processed as-is, from whoever sent it. What was meant to be opened only within the house can, depending on the router’s settings or how the internet connection is provisioned, end up reaching straight through to the outside.

What Happens When It Is Reachable from Outside

In May 2026, a vulnerability in Ollama was disclosed (CVE-2026-7482). It is a flaw in the part that loads model files, where memory gets read beyond its intended bounds. GitHub’s advisory database lists it as “out-of-bounds heap read in GGUF model loading," rated High severity.

According to the article from the company that reported it, simply sending a crafted file could leak the contents of that computer’s memory. Among the things listed as potentially exposed are the following.

The flaw itself has since been fixed. But being reachable from outside in the first place does not change just because a fix went in. The next time a different flaw turns up, the same door is still the way in.

What State Were My Own Two Machines In?

Before writing this article, I checked the two machines I have Ollama running on. This is a measurement from 5 September 2026.

Both were listening only on 127.0.0.1. Just to be sure, I tried connecting from one machine to the other, and it did not go through. Neither machine was reachable from outside.

This did not turn into a story about finding something dangerous and fixing it. But I did not know either way before I checked, so checking was still worth doing.

Three Steps to Check Your Own Setup

Every one of these steps just looks at the state of your own computer.

Step 1: Check the Address It Is Listening On

The port Ollama uses is 11434. If it shows 127.0.0.1, it is confined to your own computer; if it shows 0.0.0.0 or your computer’s IP address, it is open outward.

Step 2: Check Whether the Setting Has Been Applied

Check whether OLLAMA_HOST is set. On macOS or Linux, env | grep OLLAMA; on Windows, set OLLAMA. If nothing is printed, it is running with the default.

Step 3: Try Reaching It from Another Machine

The surest check is to actually connect from a different machine at home. Open http://(that computer's IP address):11434 in a phone’s browser, and if it shows “Ollama is running," it is reachable from inside the house.

Worth keeping in mind here: being reachable from inside the house and being reachable from outside it are two different things. If it is set up to be reachable from inside, it is also worth checking whether the router has an outward-facing hole open — port forwarding or a DMZ — for safety.

If You Want to Use It from an Outside Machine

Wanting to reach it from another machine is a natural thing to want. The company that reported the vulnerability listed three measures.

• Block outside connections to port 11434 at the router or firewall
• Put something in front of Ollama that verifies who is connecting (an authenticated proxy)
• Segment the network so the reachable range is narrower

On my own setup, I use a private network that connects machines directly to each other, and Ollama itself stays on 127.0.0.1. Whatever machine wants to use it comes in over that network instead. Deciding who can reach it first feels like an easier thing to reason about than flipping one setting and opening it in every direction.

What This Article Does Not Confirm

• I did not test the vulnerability itself. Both of my machines were unreachable from outside, and I did not attempt to reproduce the attack
• The figure of roughly 300,000 comes from the reporting company’s own investigation. It is not a number I counted myself
• I did not check the default settings of software other than Ollama, such as LM Studio

In Summary: The Range You Meant to Open, and the Range That Is Actually Open

• By default, Ollama only looks at 127.0.0.1, and left as-is, it cannot be reached from outside
• Setting OLLAMA_HOST to 0.0.0.0 opens it in every direction. Because Ollama has no mechanism to verify who is connecting, whatever request arrives gets processed as-is
• CVE-2026-7482, disclosed in May 2026, reported that when reachable from outside, typed content and keys stored in environment variables could leak. The investigation found roughly 300,000 instances reachable from outside
• Both of my own machines (a Mac mini M4, and a desktop PC with an RTX 3090 and an Intel Arc B580) listen only on 127.0.0.1. A connection attempt from the other machine also failed to go through [measured]
• Three steps to check: the listening address, whether the setting has been applied, and an actual connection attempt from another machine

One reason for keeping local LLMs at home is to avoid sending what you type anywhere outside your own machine. If the door in is left open, the largest part of the reason for keeping it at home gets thinner. Checking how far open things currently are seems worth doing at least once, on the same footing as measuring a machine’s speed or capacity.

For a look at how large a model your own computer can actually run, here is a related article.

A Mac You Can Put 512GB Into — What Changes, Seen From a 16GB Wall

3 September 2026 I had been stuck at a 16GB wall, adding an external GPU to a mini PC. Models th ...

 https://kimono-oyaji.com/mac-studio-m5-ultra-local-llm-en/

Sources

• Cyera, “Bleeding Llama: A Critical Memory Leak in the World’s Most Popular Local AI Platform" (5 May 2026; source for the vulnerability details and the number of exposed instances)
  https://www.cyera.com/blog/bleeding-llama-a-critical-memory-leak-in-the-worlds-most-popular-local-ai-platform
• GitHub Advisory Database (CVE-2026-7482; source for the severity rating and summary)
  https://github.com/advisories?query=CVE-2026-7482