HIGHCVSS 8.8Actively exploited · CISA KEV since 2026-02-10Vulnerability

CVE-2026-21513

Microsoft MSHTML Framework contains a protection mechanism failure vulnerability that could allow an unauthorized attacker to bypass a security feature over a network.

Properties

Euvd product
Windows 10 Version 21H2, Windows 10 Version 1607, Windows Server 2012 R2, Windows 11 Version 23H2, Windows Server 2019, Windows Server 2022, 23H2 Edition (Server Core installation), Windows Server 2012, Windows Server 2022, Windows 11 Version 24H2, Windows Server 2019 (Server Core installation), Windows Server 2025 (Server Core installation), Windows Server 2012 (Server Core installation), Windows Server 2016 (Server Core installation), Windows 10 Version 22H2, Windows Server 2016, Windows 10 Version 1809, Windows Server 2012 R2 (Server Core installation), Windows 11 version 22H3, Windows 11 Version 25H2, Windows Server 2025, Windows 11 version 26H1
Vulnerability name
Microsoft MSHTML Framework Protection Mechanism Failure Vulnerability
First seen
2026-08-19T16:25:57+00:00
Cvss score
8.8
Epss score
0.15852
Last seen
2026-10-19T12:00:27+00:00
Due date
2026-03-03
Euvd assigner
microsoft
Retrieved at
2026-10-21T01:24:49+00:00
Exploited euvd since
2026-02-10T00:00:00+00:00
Src batch id
epss_history-20261020T103617Z-728ddd
Source url
https://epss.empiricalsecurity.com/epss_scores-2026-10-19.csv.gz
Date added
2026-02-10
Score
8.8
Euvd base score version
3.1
Fetched at
2026-10-20T10:36:20+00:00
Euvd vendor
Microsoft
Cvss vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
In Signal since
initial import (Sep 2026)
Euvd base score
8.8

Related Entities (28 · showing 25)

AFFECTS_PRODUCT (23 · showing 20)

→[Product]cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:*
→[Product]cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
→[Product]cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
→[Product]cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:-:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:-:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*
→[Product]cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:-:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:-:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:*
→[Product]cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:*
→[Product]cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*
→[Product]cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*
→[Product]cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*
→[Product]cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*
→[Product]cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*

MENTIONED_IN (2)

→[Campaign]Unnamed campaign (ID 699e…)
→[Campaign]Inside the Fix: Analysis of In-the-Wild Exploit of CVE-2026-21513

DESCRIBES (1)

←[KEVEntry]Microsoft MSHTML Framework Protection Mechanism Failure Vulnerability

HAS_WEAKNESS (1)

→[Weakness]Protection Mechanism Failure

INVOLVES (1)

←[Signal]kev_added · 2026-02-10

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CVE-2026-21513 (CVSS 8.8) — Ninja Signal Threat Intelligence | Ninja Signal