CVE-2021-21985

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 1.000 · 100 %ileexploit · weaponizedEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 11 exploits · weaponized

Likely / severe?

100.0% (100th) EPSS

CVSS 10 · high

Is it mine?

11 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2021-11-03remediate by 2021-11-17

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-25

VMware vCenter Server Improper Input Validation Vulnerability

The vSphere Client (HTML5) contains a remote code execution vulnerability due to lack of input validation in the Virtual SAN Health Check plug-in which is enabled by default in vCenter Server. A malicious actor with network access to port 443 may exploit this issue to execute commands with unrestricted privileges on the underlying operating system that hosts vCenter Server.

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 · high–critical · 9.8–10

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

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

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

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-918USprimaryCWE-20USCWE-20USCWE-470US

exploits (11)

Public proof-of-concept and weaponised exploit code.

exploit/linux/http/vmware_vcenter_vsan_health_rceVMware vCenter Server Virtual SAN Health Check Plugin RCEweaponized · metasploit
alt3kx/CVE-2021-21985_PoCalt3kx/CVE-2021-21985_PoCPoC · poc_in_github
aristosMiliaressis/CVE-2021-21985cve-2021-21985 powershell pocPoC · poc_in_github
bigbroke/CVE-2021-21985Multiple vulnerabilities in the vSphere Client (HTML5) were privately reported to VMware. Updates and workarounds are available to address these vulnerabilities in affected VMware products.PoC · poc_in_github
daedalus/CVE-2021-21985CVE-2021-21985 vmware 6.7-9.8 RCEPoC · poc_in_github
haidv35/CVE-2021-21985haidv35/CVE-2021-21985PoC · poc_in_github

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 2026-08-12

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+4163 more

references (18)

External citations — patches, advisories, analysis.

scry

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