How severe is CVE-2021-36948?

CVE-2021-36948 has a CVSS 3.1 base score of 7.8 (HIGH). EPSS estimates a 23.3% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-36948: Windows Update Medic Service Elevation of Privilege

CISA Known Exploited Vulnerabilities

Microsoft Windows Update Medic Service Privilege Escalation Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2021-11-03

Remediation due

2021-11-17

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-36948

Description

Windows Update Medic Service Elevation of Privilege Vulnerability

Severity

CVSS 3.1 · CNA7.8 HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impacttotal

Exploitation Context

as of October 14, 2026

All KEV statistics→

CISA added CVE-2021-36948 to the KEV catalog 83 days after its CVE record was published.
It is one of 391 Microsoft entries in the CISA KEV catalog, and one of 83 added in 2021.
Its current EPSS score (23.3%) is higher than that of 37% of CISA KEV entries.

Affected Products

Vendor	Product	Affected versions
Microsoft	Microsoft Windows 10 Version 1809	10.0.17763.0 to <10.0.17763.2114
Microsoft	Microsoft Windows 10 Version 1809	10.0.0 to <10.0.17763.2114
Microsoft	Microsoft Windows 10 Version 1909	10.0.0 to <10.0.18363.1734
Microsoft	Microsoft Windows 10 Version 2004	10.0.0 to <10.0.19041.1165
Microsoft	Microsoft Windows 10 Version 20H2	10.0.0 to <10.0.19042.1165
Microsoft	Microsoft Windows 10 Version 21H1	10.0.0 to <10.0.19043.1165
Microsoft	Microsoft Windows Server 2019	10.0.17763.0 to <10.0.17763.2114
Microsoft	Microsoft Windows Server 2019 (Server Core installation)	10.0.17763.0 to <10.0.17763.2114
Microsoft	Microsoft Windows Server version 2004	10.0.0 to <10.0.19041.1165
Microsoft	Microsoft Windows Server version 20H2	10.0.0 to <10.0.19042.1165

References

2 Links

Vendor advisories

Windows Update Medic Service Elevation of Privilege Vulnerability

Other references

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36948

Record Details

Published

2021-08-12

Last updated

2026-08-10

Assigner (CNA)

microsoft

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.