Microsoft MSHTML Framework Protection Mechanism Failure Vulnerability

Microsoft Windows

Microsoft MSHTML Framework contains a protection mechanism failure vulnerability that could allow an unauthorized attacker to bypass a security feature over a network. Can be chained with CVE-2026-21525, CVE-2026-21510, CVE-2026-21533, CVE-2026-21519. Added to CISA KEV on 2026-02-10 (federal deadline 2026-03-03).

First seen: 10 Feb 2026
Last update: 10 Feb 2026, 12:00 UTC
Identifiers: CVE-2026-21510
CVE-2026-21513
CVE-2026-21519
CVE-2026-21525
CVE-2026-21533
Source: CISA KEV
On the menu as: Windows

Check this repository for exposure to one security incident from pwned.coffee. Report first, change nothing until I say so.

## Microsoft MSHTML Framework Protection Mechanism Failure Vulnerability
Severity: high, exploited in the wild. Patch status: patched.
Affected: Microsoft Windows
Ids: CVE-2026-21510, CVE-2026-21513, CVE-2026-21519, CVE-2026-21525, CVE-2026-21533

Microsoft MSHTML Framework contains a protection mechanism failure vulnerability that could allow an unauthorized attacker to bypass a security feature over a network. Can be chained with CVE-2026-21525, CVE-2026-21510, CVE-2026-21533, CVE-2026-21519. Added to CISA KEV on 2026-02-10 (federal deadline 2026-03-03).

## Steps
1. This touches infrastructure (windows). Look in terraform, ansible, cloud-init, Dockerfiles and docs for the product and version we run. If it isn't in the repo, say so and list what a human should check on the box.

## Report
A table: file, product or package, version in use, affected yes/no, exact fix. Then anything a human has to check outside the repo.

If you have the pwned.coffee MCP server (https://pwned.coffee/mcp), call lookup_cve("CVE-2026-21510") for the latest, and check_repo with this repo's lockfiles, Dockerfiles and workflows for a full receipt.
Sources: https://msrc.microsoft.com/update-guide/advisory/CVE-2026-21513 https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21510 https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21519 https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21525 https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21533 https://nvd.nist.gov/vuln/detail/CVE-2026-21510 https://nvd.nist.gov/vuln/detail/CVE-2026-21513 https://nvd.nist.gov/vuln/detail/CVE-2026-21519 https://nvd.nist.gov/vuln/detail/CVE-2026-21525 https://nvd.nist.gov/vuln/detail/CVE-2026-21533
https://pwned.coffee/i/microsoft-mshtml-framework-protection-mechanism-failure-vulnerability

Sources

Totalone hot coffee