CVE-2021-21973

mediumpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.880 · 100 %ileexploit · PoCEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 1 exploit · PoC

Likely / severe?

88.0% (100th) EPSS

CVSS 5 · medium

Is it mine?

15 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2022-03-07remediate by 2022-03-21

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-26

VMware vCenter Server and Cloud Foundation Server Side Request Forgery (SSRF) Vulnerability

The vSphere Client (HTML5) contains an SSRF (Server Side Request Forgery) vulnerability due to improper validation of URLs in a vCenter Server plugin. A malicious actor with network access to port 443 may exploit this issue by sending a POST request to vCenter Server plugin leading to information disclosure. This affects: VMware vCenter Server (7.x before 7.0 U1c, 6.7 before 6.7 U3l and 6.5 before 6.5 U3n) and VMware Cloud Foundation (4.x before 4.2 and 3.x before 3.10.1.2).

cvss

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

5.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.15.3mediumAV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nsecondary · FSTEC (BDU) RU

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nsecondary · ENISA EU

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nsecondaryexploitability 3.9 · impact 1.4

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:Hsecondary · CVSS-BT (t0sche)

ssvc

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

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

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-918USprimaryCWE-918US

ATT&CK techniques

ATT&CK techniques this enables or maps to.

exploits (1)

Public proof-of-concept and weaponised exploit code.

freakanonymous/CVE-2021-21973-Automatemeautomate me!PoC · poc_in_github

affected products (15)

Products and version ranges known to be affected.

n/a VMware Cloud Foundation≤ 4.x before 4.2enisa_euvdEU
n/a VMware Cloud Foundation≤ 3.x before 3.10.1.2enisa_euvdEU
n/a VMware vCenter Server≤ 6.5 before 6.5 U3nenisa_euvdEU
n/a VMware vCenter Server≤ 6.7 before 6.7 U3lenisa_euvdEU
n/a VMware vCenter Server≤ 7.x before 7.0 U1cenisa_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 Server6.5 → 6.5 U3nfstec_bduRU
Broadcom Inc. VMware vCenter Server6.7 → 6.7 U3lfstec_bduRU
Broadcom Inc. VMware vCenter Server7.0 → 7.0 U1cfstec_bduRU
vmware cloud foundation3.0 → 3.10.1.2nvdUScpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
vmware cloud foundation4.0 → 4.2nvdUScpe: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 2021-02-24modified 2026-06-17

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+4166 more

references (9)

External citations — patches, advisories, analysis.

scry

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