Skip to main content
Public proof of conceptFix available

CVE-2026-20817

A public proof of concept exists; no exploitation attested.

  • Published2026-01-13
  • Fixed in10.0.19044.6809
  • WeaknessCWE-280

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

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

Timeline

dates in UTC
  1. 2026-01-1318:16CVE publishedNVD

Versions per branch

NVD
Microsoft windows 10 21h2
BranchAffectedFixed in
10.0< 10.0.19044.680910.0.19044.6809
Microsoft windows 10 22h2
BranchAffectedFixed in
10.0< 10.0.19045.680910.0.19045.6809
Microsoft windows 11 23h2
BranchAffectedFixed in
10.0< 10.0.22631.649110.0.22631.6491

5 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA10 products

As microsoft, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

  • Microsoft Windows 10 Version 21H2

    platforms: 32-bit Systems, ARM64-based Systems, x64-based Systems

    Affected
    • ≥ 10.0.19044.0, < 10.0.19044.6809fixed in 10.0.19044.6809custom
  • Microsoft Windows 10 Version 22H2

    platforms: 32-bit Systems, ARM64-based Systems, x64-based Systems

    Affected
    • ≥ 10.0.19045.0, < 10.0.19045.6809fixed in 10.0.19045.6809custom
  • Microsoft Windows 11 version 22H3

    platforms: ARM64-based Systems

    Affected
    • ≥ 10.0.22631.0, < 10.0.22631.6491fixed in 10.0.22631.6491custom
  • Microsoft Windows 11 Version 23H2

    platforms: x64-based Systems

    Affected
    • ≥ 10.0.22631.0, < 10.0.22631.6491fixed in 10.0.22631.6491custom
  • Microsoft Windows 11 Version 24H2

    platforms: ARM64-based Systems, x64-based Systems

    Affected
    • ≥ 10.0.26100.0, < 10.0.26100.7623fixed in 10.0.26100.7623custom
  • Microsoft Windows 11 Version 25H2
    Affected
    • ≥ 10.0.26200.0, < 10.0.26200.7623fixed in 10.0.26200.7623custom

4 more products in the CVE record.

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2026-04-01

Fix

  1. Update Microsoft windows 10 21h2 to 10.0.19044.6809

Advisories and patches

Detection

read 2026-11-06 06:14 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Published
2026-01-13
Last Modified
2026-07-30
NVD status
Modified
GitHub Advisory
GHSA-p4qh-cj7j-r785

Frequently asked questions

What is CVE-2026-20817?

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

Is CVE-2026-20817 actively exploited?

Active exploitation of CVE-2026-20817 has not been confirmed. Its EPSS score was 5.4% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-20817?

CVE-2026-20817 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Hear about the next vulnerability in your software

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, November 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record