---
title: "Microsoft Copilot had a secret input that let hackers steal passwords"
url: https://www.parallelquant.com/posts/microsoft-copilot-had-a-secret-input-that-let-hackers-steal-passwords-cb51e0
source_name: "Ars Technica"
source_url: https://arstechnica.com/security/2026/08/microsoft-copilot-reveals-secret-input-that-allowed-it-to-be-hacked/
published: 2026-08-18T13:00:04.000Z
topics: ["products"]
publisher: "Parallel Quant"
---

# Microsoft Copilot had a secret input that let hackers steal passwords

*2026-08-18 · Source: [Ars Technica](https://arstechnica.com/security/2026/08/microsoft-copilot-reveals-secret-input-that-allowed-it-to-be-hacked/)*

A hidden parameter in Microsoft Copilot allowed attackers to steal user passwords when a target clicked a malicious link, according to Ars Technica.

**Why it matters:** As AI assistants get deeper access to enterprise data and credentials, undocumented parameters become a serious attack surface. Vulnerabilities like this could scale quickly given Copilot's integration across Microsoft's enterprise products.

**Topics:** products

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Read the original: https://arstechnica.com/security/2026/08/microsoft-copilot-reveals-secret-input-that-allowed-it-to-be-hacked/
Canonical: https://www.parallelquant.com/posts/microsoft-copilot-had-a-secret-input-that-let-hackers-steal-passwords-cb51e0
Published by Parallel Quant — https://www.parallelquant.com