Cyber Resilience

CVE-2021-43893

HighPublic PoC

Published: 15 December 2021

Published
15 December 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0676 91.5th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-43893 is a high-severity Exposure of Resource to Wrong Sphere (CWE-668) vulnerability in Microsoft Windows 10. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 8.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Windows Encrypting File System (EFS) Elevation of Privilege Vulnerability

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

microsoft
windows 10
1607, 1809, 1909, 2004, 20h2
microsoft
windows 11
all versions
microsoft
windows 7
all versions
microsoft
windows 8.1
all versions
microsoft
windows rt 8.1
all versions
microsoft
windows server
2022, 20h2
microsoft
windows server 2008
r2
microsoft
windows server 2012
all versions, r2
microsoft
windows server 2016
2004, all versions
microsoft
windows server 2019
all versions

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-668

Controls whether organization resources are exposed to external system spheres by permitting or prohibiting their use.

addresses: CWE-668

The control ensures information is not released into a security sphere where the recipient lacks matching access authorizations.

addresses: CWE-668

The control ensures information resources are not exposed to the incorrect (public) sphere through review and authorization.

addresses: CWE-668

Protects against data mining that would expose resources to unauthorized spheres by enforcing detection and controls.

addresses: CWE-668

Restricts information flows to ensure resources are not exposed to incorrect or unauthorized spheres.

addresses: CWE-668

Controlling internal connections prevents exposure of resources to unintended internal spheres.

addresses: CWE-668

Knowing exact processing and storage locations helps avoid exposure of resources to incorrect spheres.

addresses: CWE-668

The control prevents exposure of the media resource to the wrong security sphere.

References