What is CVE-2026-21520?

CVE-2026-21520 is a security advisory published by Microsoft Security Response Center (MSRC) with Critical severity. Copilot Studio Information Disclosure Vulnerability

Which CVE IDs does CVE-2026-21520 cover?

CVE-2026-21520 covers the following CVE IDs: CVE-2026-21520. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-21520?

CVE-2026-21520 has a CVSS v3 base score of 7.5, published by Microsoft Security Response Center (MSRC).

Which products are affected by CVE-2026-21520?

CVE-2026-21520 affects 1 product, including: Microsoft Copilot Studio.

CVE-2026-21520CriticalCVSS 7.5

Copilot Studio Information Disclosure Vulnerability

Vendor

Microsoft Security Response Center (MSRC)

Published

June 2, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-21520 →

📋 Description

Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive information through network attack vector

🎯 Affected products1

Microsoft Copilot Studio

🔗 References (1)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21520