vciy

CVE-2021-21985

INDEX BUILT · 2026-09-20

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The vSphere Client (HTML5) contains a remote code execution vulnerability due to lack of input validation in the Virtual SAN Health Check plug-in…

CVE-2021-219854 of 4 sources documented this
77

rank 77 = 40 + 25 + 0 + 6 + 6

rank@v1 · act now

Someone is already using it

CISA KEV catalog · public proof-of-concept · FIRST EPSS

EPSS 0.99999 · CISA KEV listed  ·  without this subject the record ranks 37

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 9.8, from NVD  ·  without this subject the record ranks 52

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

no persisting rise in 365 days  ·  without this subject the record ranks 77

How much of the world it touches

NVD CPE configurations

5 products in the CPE ranges  ·  without this subject the record ranks 71

Someone else already set the date

CISA KEV remediation due date

CISA remediation date held  ·  without this subject the record ranks 71

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$4.99Mover the next 30 days, if this record is yours
Movement+$2.83Mon 2022-02-04, the last material move, 4 years, 7 months before this reading
Basisassumeda published average, not your estate

$4.99M = $4.99M incident cost x 1 exposure x 0.99999 likelihood

udv@v1 · unaudited · wrong for you until you say what you run

$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.

Hindsight · the state

0.99999EPSSKEV · LISTED
Severity9.8 CRITICALreceipt
Harmtotal loss · unauthenticated · ransomware-linkedreceipt
Exploitationransomware use knownreceipt
Defenseunaffected versions publishedreceipt
Movementscoring model changedreceipt
PLATEAU10Minimal movement since 2022-02-04, 1673 days at 1.00, as of 2026-09-04. arc-rules@v1

Foresight · where to check next

CVE-2021-27103CVE-2020-7796BIG-IPSonicWall SMA1000MicrosoftVMware vRealize21985

This record is one instance of CWE-918, server-side request forgery (ssrf). The index holds 3591 prior instances of this class, 23 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1

Full pattern panel

Prior records in this weakness class. Each is its own record, dated and receipted.
Color is a claim, not decoration:the hostile worldthe defenseno signalspoke length is how much of the record matches, not how bad it is

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Harm, if it fires from the vector and the weakness

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Reachnetwork-reachable · no privileges required · no user interaction · low attack complexityreceipt
ImpactComplete confidentiality, integrity and availability lossreceipt
Scored fromCVSS v3.1 · NVD's vectorreceipt
Weakness classCWE-918 Server-Side Request Forgery (SSRF); CWE-20 Improper Input Validation; CWE-470 Use of Externally-Controlled Input to Select Classes or Code…receipt
Published consequencesCWE-918: Confidentiality: Read Application Data; Integrity: Execute Unauthorized Code or Commands; Access Control: Bypass Protection Mechanism[email protected]
Ransomware campaign useKnown (CISA)receipt

CISA KEV & Federal Remediation Deadline from the record and CISA

The fix, and how long it's been waiting.

First unaffected version, by branchcloud foundation 3.10.2.1; cloud foundation 4.2.1receipt
Patch available sinceNo dated patch-availability record in held sources. The index holds reference URLs without dates and only the current revision of the CVE record, so the day a fix first existed cannot be derived. Only the versions it landed in.
CISA remediation statusoverdue since 2021-11-17receipt
CISA required actionApply updates per vendor instructions.receipt
Published to CISA KEV161 daysderived

Exploit Status & Known PoCs a ladder, not a score

Current rung: Ransomware campaign use known, 2021-11-03.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published · 10 public repositories2021-05-27receipt
  • RUNG 3Exploited in the wild · CISA KEV listed2021-11-03receipt
  • RUNG 4Ransomware campaign use known2021-11-03receipt

Authority who says so

CVSS, NVD9.8 CRITICALreceipt
Exploit probability0.99999 · top 0.01% of all CVEsreceipt
Blast breadth2 products across 1 vendorderived
Assigned byvmwarereceipt
Recorded changes53 · last 17 Sep 2026derived

Affected & Fixed Versions as published

Affected productVMware vCenter Server and VMware Cloud Foundationreceipt
Published rangesvmware vcenter server 6.5; vmware vcenter server 6.7; vmware vcenter server 7.0; vmware cloud foundation >= 3.0 < 3.10.2.1receipt
Show all 5 published ranges
vmware vcenter server 6.5
vmware vcenter server 6.7
vmware vcenter server 7.0
vmware cloud foundation >= 3.0 < 3.10.2.1
vmware cloud foundation >= 4.0 < 4.2.1

A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.

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What it is stated by the CNA

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. receipt

NVD's analysis a second authority

severity
9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
weakness
CWE-918; CWE-20; CWE-470
affected versions
vmware vcenter server 6.5; vmware vcenter server 6.7; vmware vcenter server 7.0; and 2 more, listed in full below
also scored by
9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

check it yourself vmware.com packetstormsecurity.com packetstormsecurity.com receipt

Dated events

2021-07-13EPSS moved 0.06 to 0.322021-11-03Added to CISA KEV2021-11-17CISA remediation due2022-02-04EPSS moved 0.38 to 0.952026-06-15EPSS moved 0.94 to 1.00

Movement the material steps

27 May 20210.01374
13 Jul 20210.31602 · crossed 0.10
4 Feb 20220.94936 · crossed 0.50 and 0.90
7 Mar 20230.97465 · scoring model v2023.03.01
17 Mar 20250.9437 · scoring model v2025.03.14
15 Jun 20260.99999 · scoring model v2026.06.15
Show all 39 observations
27 May 20210.01374
31 May 20210.05885
13 Jul 20210.31602
14 Jul 20210.3817
4 Feb 20220.94936
16 Apr 20220.95312
7 Mar 20230.97465
15 Mar 20230.97455
29 Mar 20230.97409
25 Apr 20230.97450
11 May 20230.97480
6 Jul 20230.97475
8 Jul 20230.97460
18 Aug 20230.97454
22 Sep 20230.97370
22 Nov 20230.97310
5 Dec 20230.97396
31 Dec 20230.97380
14 Jan 20240.97410
27 Jan 20240.97387
7 Feb 20240.97445
9 Feb 20240.97407
17 Apr 20240.97389
1 May 20240.97361
14 May 20240.97371
12 Jun 20240.97395
12 Aug 20240.97415
11 Sep 20240.97435
28 Sep 20240.97454
13 Oct 20240.97387
29 Oct 20240.97429
3 Dec 20240.97387
17 Dec 20240.97397
7 Jan 20250.97423
17 Mar 20250.9437
7 Nov 20250.94412
18 Nov 20250.94374
21 Nov 20250.94412
15 Jun 20260.99999

39 observations held. A highlighted step crossed a promotion threshold. A step marked with a scoring model moved because the instrument was replaced, not because the vulnerability changed. receipt

The full biography

EPSS 0.99999Published2021-05-26Public PoC2021-05-27CISA KEV2021-11-03Index as of2026-09-04

Listed by CISA 161 days after it published and the record had been public for 5 years, 3 months when this index was last written.

No material movement in 81 days as of the last ingest this index recorded.

Published 2021-05-26 receipt · Public PoC 2021-05-27 receipt · CISA KEV 2021-11-03 receipt · Index as of 2026-09-04 derived

The pattern, elsewhere

This record is one instance of CWE-918, server-side request forgery (ssrf). The index holds 3591 prior instances of this class, 23 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]

CVE-2021-27103matches 8 of 9KEV listed · 2021receipt
CVE-2020-7796matches 8 of 9KEV listed · 2020receipt
CVE-2021-22986 · BIG-IPmatches 8 of 10KEV listed · 2021receipt
CVE-2026-15409 · SonicWall SMA1000matches 7 of 10KEV listed · 2026receipt
CVE-2022-41040 · Microsoft Exchange Server 2013 Cumulative…matches 7 of 10KEV listed · 2022receipt
CVE-2021-21975 · VMware vRealize Operationsmatches 7 of 10KEV listed · 2021receipt

"Matches n of m" counts the attributes the two records can both be compared on: the CVSS metrics they share a version of, any weakness class beyond this one, and the vendor. fit-rules@v1

3591 records in this class held. The six above are drawn from the ones CISA has listed as exploited, ranked by how much of the record matches this one. That is why every one of them is KEV-listed: the pool is, so the colour on those spokes says nothing the pool has not already said.

No curated product neighbourhood is held for this product, so the records above are the nearest this index can name. The neighbourhood table covers a small set of products and is extended by hand.

Siblings and hubs

Records related to this one

Its defect family

vmware vcenter server

Of the 4 records in this family, this is the only one holding a CISA KEV listing: VMware vCenter Server Improper Input Validation Vulnerabilit.

Grouped by shared product and weakness, not by shared vulnerability. Each record's own state is on its own page.

Family membership: computed, pro@dim2000

This record is one of a group, and the group's page describes all of them. This page is kept and dated, and the defect family's own page is the one we offer for indexing: the whole group.

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