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Vulnerability record · CVE-2026-20817 · published 13 January 2026

CVE-2026-20817: Microsoft windows 10 21h2 vulnerability

Microsoft · Windows 10 21h2

Improper handling of insufficient permissions or privileges in Windows Error Reporting allows an authorized attacker to elevate privileges locally.

7.8 CVSS 3.1 High EPSS 5.5% · top 7.5% CWE-280 · CWE-280
7.8CVSS 3.1 base score
5.5%EPSS exploitation probability, 30 days
NoNot in CISA KEV
8Affected product versions listed by NVD
3References
30 Jul 2026Last modified by NVD

Description

Improper handling of insufficient permissions or privileges in Windows Error Reporting allows an authorized attacker to elevate privileges locally.

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

Affected products

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

References

LinkTags
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20817 Vendor Advisory
https://www.vicarius.io/vsociety/posts/cve-2026-20817-detection-script-eop-vulnerabilit-in-windows-error-reporting
https://www.vicarius.io/vsociety/posts/cve-2026-20817-mitigation-script-eop-vulnerability-in-windows-error-reporting

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

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Source: NIST National Vulnerability Database (record CVE-2026-20817), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.