CVE-2026-21520

Name: CVE-2026-21520
Creator: NVD / NIST
Published: 2026-01-22T23:15:57.657+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.40%

Last modified Jun 17, 2026

CVE-2026-21520 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive information through network attack vector. EPSS estimates a 1.40% chance of exploitation in the next 30 days.

Description

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

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

1.40%

69.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-77

Affected Software

Vendor	Product	Versions
Microsoft	Copilot Studio	All versions

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21520Vendor Advisory

Timeline

Published: Jan 22, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-21520?

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

How severe is CVE-2026-21520?

CVE-2026-21520 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.40% probability of exploitation in the next 30 days.

How do I fix CVE-2026-21520?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-21520?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST