Microsoft

CVE-2022-21907: HTTP Protocol Stack Remote Code Execution Vulnerability

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of 29 Oct 2026.

VulnCheck KEV lists it since 7 May 2024. It cites 2 public reports, the first from 7 May 2024.

How likely is exploitation in the next 30 days?

92.8%

EPSS score, percentile 99.8 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

9.8 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

Advisories and patches (1)

Which versions are affected?

Affected

from 10.0.17763.0 to before 10.0.17763.2452
from 10.0.0 to before 10.0.17763.2452
from 10.0.17763.0 to before 10.0.17763.2452
from 10.0.17763.0 to before 10.0.17763.2452
from 10.0.0 to before 10.0.19043.1466
from 10.0.20348.0 to before 10.0.20348.469

and 4 more in the table below

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; VulnCheck KEV, as of 30 Oct 2026; FIRST EPSS, as of 30 Oct 2026; CVE List, as of 30 Oct 2026. About the data.

Description

HTTP Protocol Stack Remote Code Execution Vulnerability

HTTP Protocol Stack Remote Code Execution Vulnerability

Source: CVE List, as of 30 Oct 2026. About the data.

What to do

Advisories and patches

HTTP Protocol Stack Remote Code Execution Vulnerability (Vendor advisory)

This summary is based on the CVE record as of 30 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Versions by product, as listed in the CVE record (10 products)

Microsoft Windows 10 Version 1809
Status	Versions
Affected	from 10.0.17763.0 to before 10.0.17763.2452

Microsoft Windows 10 Version 1809
Status	Versions
Affected	from 10.0.0 to before 10.0.17763.2452

Microsoft Windows Server 2019
Status	Versions
Affected	from 10.0.17763.0 to before 10.0.17763.2452

Microsoft Windows Server 2019 (Server Core installation)
Status	Versions
Affected	from 10.0.17763.0 to before 10.0.17763.2452

Microsoft Windows 10 Version 21H1
Status	Versions
Affected	from 10.0.0 to before 10.0.19043.1466

Microsoft Windows Server 2022
Status	Versions
Affected	from 10.0.20348.0 to before 10.0.20348.469

Microsoft Windows 10 Version 20H2
Status	Versions
Affected	from 10.0.0 to before 10.0.19042.1466

Microsoft Windows Server version 20H2
Status	Versions
Affected	from 10.0.0 to before 10.0.19042.1466

Microsoft Windows 11 version 21H2
Status	Versions
Affected	from 10.0.0 to before 10.0.22000.434

Microsoft Windows 10 Version 21H2
Status	Versions
Affected	from 10.0.19043.0 to before 10.0.19044.1466

Source: CVE List, as of 30 Oct 2026. About the data.

Timeline

Date	Event
11 Jan 2022	CVE record published
2 Jan 2025	CVE record last updated

Known exploited Microsoft vulnerabilities

CVE-2026-96951: Microsoft Windows Command Injection Vulnerability (added 13 Oct 2026)
CVE-2026-65660: Microsoft SharePoint Code Injection Vulnerability (added 25 Sep 2026)
CVE-2026-81963: Microsoft Windows Link Following Vulnerability (added 8 Sep 2026)
CVE-2026-85880: Microsoft Windows Heap-Based Buffer Overflow Vulnerability (added 8 Sep 2026)
CVE-2019-1068: Microsoft SQL Server Remote Code Execution Vulnerability (added 26 Aug 2026)