CVE-2021-21986

highpriority · track · 44OT risk · elevatedEPSS 0.133 · 96 %ileEURUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

13.3% (96th) EPSS

CVSS 10 · high

Is it mine?

11 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-25

The vSphere Client (HTML5) contains a vulnerability in a vSphere authentication mechanism for the Virtual SAN Health Check, Site Recovery, vSphere Lifecycle Manager, and VMware Cloud Director Availability plug-ins. A malicious actor with network access to port 443 on vCenter Server may perform actions allowed by the impacted plug-ins without authentication.

cvss

Technical severity, 0–10. One row per scoring source.

10.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6.5–10

v2.010highAV:N/AC:L/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 10 · impact 10

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.16.5mediumAV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-306USprimaryCWE-287US

affected products (11)

Products and version ranges known to be affected.

n/a VMware vCenter Server and VMware Cloud Foundation≤ VMware vCenter Server (7.x before 7.0 U2b, 6.7 before 6.7 U3n, 6.5 before 6.5 U3p) and VMware Cloud Foundation (4.x before 4.2.1, 3.x before 3.10.2.1)enisa_euvdEU
Broadcom Inc. VMware Cloud Foundation3.0 → 3.10.1.2fstec_bduRU
Broadcom Inc. VMware Cloud Foundation4.0 → 4.2fstec_bduRU
Broadcom Inc. VMware vCenter Server≤ 6.7fstec_bduRU
Broadcom Inc. VMware vCenter Server≤ 7.0fstec_bduRU
Broadcom Inc. VMware vCenter Server≤ 6.5fstec_bduRU
vmware cloud foundation3.0 → 3.10.2.1nvdUScpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
vmware cloud foundation4.0 → 4.2.1nvdUScpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
vmware vcenter server= 6.5nvdUScpe:2.3:a:vmware:vcenter_server:*:*:*:*:*:*:*:*
vmware vcenter server= 6.7nvdUScpe:2.3:a:vmware:vcenter_server:*:*:*:*:*:*:*:*
vmware vcenter server= 7.0nvdUScpe:2.3:a:vmware:vcenter_server:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-05-26modified 2026-06-17

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+4421 more

references (13)

External citations — patches, advisories, analysis.

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