Live › vulnerability › CVE-2026-21513
Go to dashboardMicrosoft MSHTML Framework, the browser rendering engine used by Windows, has a protection mechanism failure that lets an unauthenticated attacker bypass a security feature over the network. CISA lists it as actively exploited in the wild.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 5h before NVD. All times on this page are UTC.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| Microsoft Windows | vendor | – | – |
| microsoft windows 10 1607 | vendor | < 10.0.14393.8868 | 10.0.14393.8868 |
| microsoft windows 10 1809 | vendor | < 10.0.17763.8389 | 10.0.17763.8389 |
| microsoft windows 10 21h2 | vendor | < 10.0.19044.6937 | 10.0.19044.6937 |
| microsoft windows 10 22h2 | vendor | < 10.0.19045.6937 | 10.0.19045.6937 |
| microsoft windows 11 23h2 | vendor | < 10.0.22631.6649 | 10.0.22631.6649 |
| microsoft windows 11 24h2 | vendor | < 10.0.26100.7781 | 10.0.26100.7781 |
| microsoft windows 11 25h2 | vendor | < 10.0.26200.7781 | 10.0.26200.7781 |
| microsoft windows server 2012 | vendor | – | – |
| microsoft windows server 2012 | vendor | = r2 | – |
| microsoft windows server 2016 | vendor | < 10.0.14393.8868 | 10.0.14393.8868 |
| microsoft windows server 2019 | vendor | < 10.0.17763.8389 | 10.0.17763.8389 |
| microsoft windows server 2022 | vendor | < 10.0.20348.4711 | 10.0.20348.4711 |
| microsoft windows server 2022 23h2 | vendor | < 10.0.25398.2149 | 10.0.25398.2149 |
| microsoft windows server 2025 | vendor | < 10.0.26100.32313 | 10.0.26100.32313 |
Unknown from the sources.
Apply the Microsoft security update for CVE-2026-21513 per vendor instructions; if no mitigation is available, discontinue use of the affected product (per CISA guidance).
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Microsoft MSHTML Framework contains a protection mechanism failure vulnerability that could allow an unauthorized attacker to bypass a security feature over a network.
CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
This page as .md · .json · in your agent: get_signal("CVE-2026-21513")
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