CVE-2026-54130 M365 Copilot Information Disclosure Vulnerability

Critical 9.8 Published 18 Jun 2026 Updated 24 Sep 2026

An unauthorized attacker can disclose information over the network due to missing authentication in Microsoft 365 Copilot.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-54130?

CVE-2026-54130 is a critical missing authorization vulnerability in Microsoft 365 Copilot, published on 18 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to disclose information over a network.

Weakness: CWE-306

Which versions are affected by CVE-2026-54130?

It affects 1 product.

Products include Microsoft 365 Copilot.

How do I fix CVE-2026-54130?

No fix has been published for CVE-2026-54130 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-54130 being exploited?

There is no known exploitation of CVE-2026-54130 in the wild and no public exploit code.

All Microsoft 365 Copilot vulnerabilities

Sources

Also known as GHSA-9cqp-hgpj-49wr.