CVE-2021-21994

CRITICALImmediate

Published:Jul 13, 2021(4 years ago)

Modified:Oct 31, 2025

Remote ExploitNo Auth RequiredNo InteractionLow Complexity

Vulnerability Description

SFCB (Small Footprint CIM Broker) as used in ESXi has an authentication bypass vulnerability. A malicious actor with network access to port 5989 on ESXi may exploit this issue to bypass SFCB authentication by sending a specially crafted request.

Attack Characteristics

Network AccessLow ComplexityNo Auth NeededNo User Interaction

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AI analysis not yet available

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No Fix Known

No patch has been released yet. Apply workarounds or mitigations where available.

Affected Software

238

Vendor	Product	Versions	Fixed In
vmware	cloud_foundation	3.0 - 3.10.2	-
vmware	cloud_foundation	4.0 - 4.3	-
vmware	esxi	-

Timeline

Published
CVE disclosed publicly
Jul 13, 20214 years ago
Last Modified
Most recent update
Oct 31, 20256 months ago
Indexed to CVEInsight
Added to this platform
Mar 29, 20261 month ago

References

https://www.vmware.com/security/advisories/VMSA-2021-0014.htmlVendor Advisory
https://www.vmware.com/security/advisories/VMSA-2021-0014.htmlVendor Advisory

CVSS Score

v3.1

9.8/ 10.0

CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

At a Glance

238

Affected Products

References

vmware / cloud_foundation

CVE-2021-21994

Vulnerability Description

Attack Characteristics

Affected Software

Timeline

References

CVSS Score

At a Glance

Official Sources

CVSS v3 Vector

Impact Analysis

CVE-2021-21994

✦ Vulnerability Description

Attack Characteristics

Affected Software

Timeline

References

CVSS Score

At a Glance

Official Sources

CVSS v3 Vector

Impact Analysis

Vulnerability Description