Muse is Meta's new AI agent. It can write documents, fill in forms and keep track of tasks, and it has a share button. Press it and Muse makes a web link, so a colleague or friend can open the page. Only people with the link are supposed to see it.

This week, researchers at the security firm Claroc showed that was not quite true. They found about 6,800 of those links without anyone sending them a single one. "It took one query," they wrote.

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What was inside

The researchers opened a few hundred of the pages. According to Ars Technica, they included a small business owner's loan application with the amount requested, a marketing company's internal revenue review marked for its CEO, a to-do list with a bank fraud alert and part of an account number, and a workplace's full year holiday calendar listing dozens of staff.

How the links leaked

Every website address has to be looked up in the internet's address book, called DNS, before it opens. Some companies keep records of those lookups and sell searches of them. Muse put the title of each shared page into the front of its address, for example something like "loan-application-draft" followed by a random code. Once the link was opened, that address could end up in those searchable records, title and all.

So the page name told the researchers what was inside before they even clicked.

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What Meta did

Meta paused the share feature on 20 October after Ars Technica asked about it. On 22 October, Meta's David Singleton said on X that "the underlying issue is now fixed, and sharing is back on." He said the problem affected shared documents and images inside Muse, not chat sharing. Old links now show a note asking visitors to get a new link from the person who shared it.

It is not the first time. The Verge notes that shared chats from ChatGPT, Claude and Grok have turned up in Google search before.

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Why it matters

More of us are handing AI agents our email, calendars and bank details so they can do jobs for us. A share link feels private, like handing someone an envelope. But "anyone with the link" can mean more people than we think. Before sharing anything an AI made, it is worth asking: would it be fine if a stranger read it?

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