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Vulnerability record · CVE-2026-80098 · published 3 September 2026

CVE-2026-80098: Microsoft copilot studio improper verification of cryptographic signature vulnerability

Microsoft · Copilot Studio

Improper verification of cryptographic signature in Copilot Studio allows an unauthorized attacker to elevate privileges over a network.

10.0 CVSS 3.1 Critical EPSS 0.49% · top 60.5% CWE-347 · Improper verification of cryptographic signature
10.0CVSS 3.1 base score
0.49%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References
8 Sep 2026Last modified by NVD

Description

Improper verification of cryptographic signature in Copilot Studio allows an unauthorized attacker to elevate privileges over a network.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80098 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-80098), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.