Is CVE-2021-21978 actively exploited?

Yes. KEV Intelligence tracks CVE-2021-21978 as a known exploited vulnerability. Confidence is high.

What exploitation activity has KEV Intelligence observed?

KEV Intelligence has not yet recorded sensor-observed exploitation attempts for CVE-2021-21978. Our sensors continue to monitor for activity targeting this CVE.

Which versions are affected?

CVE-2021-21978 affects VMware VMware View Planner. Reported affected version: VMware View Planner 4.x prior to 4.6 Security Patch 1.

No. CVE-2021-21978 is not currently listed in CISA KEV.

Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2021-21978

VMware View Planner Remote Code Execution

VMware / VMware View Planner · VMware View Planner 4.x prior to 4.6 Security Patch 1

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Severity: CVSS 9.8 · Critical
Confidence: High
Exploit status: Exploited in the wild
EPSS: 99.0%
First observed: —
Last observed: —

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2021-21978 is an unauthenticated vulnerability affecting VMware VMware View Planner. VMware View Planner 4.x prior to 4.6 Security Patch 1 contains a remote code execution vulnerability. Improper input validation...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is high.

Who is affected?

VMware / VMware View Planner vmware view planner 4.x prior to 4.6 security patch 1.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

VMware View Planner 4.x prior to 4.6 Security Patch 1 contains a remote code execution vulnerability

VMware View Planner 4.x prior to 4.6 Security Patch 1 contains a remote code execution vulnerability. Improper input validation and lack of authorization leading to arbitrary file upload in logupload web application.

An unauthorized attacker with network access to View Planner Harness could upload and execute a specially crafted file leading to remote code execution within the logupload container.

Vendor Product Affected Status

n/a VMware View Planner VMware View Planner 4.x prior to 4.6 Security Patch 1 Affected

Published: 03 Mar 2021
Exploitation Reported: 22 Apr 2025
Attack vector: Remote
Complexity: Low
Privileges: None
User interaction: None

CVE References

CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2021-21978
vmware.com/security/advisories/VMSA-2021-0003.html vmware.com · CVE Record https://www.vmware.com/security/advisories/VMSA-2021-0003.html
packetstormsecurity.com/files/161879/VMware-View-Planner-4.6-Remote-... packetstormsecurity.com · CVE Record http://packetstormsecurity.com/files/161879/VMware-View-Planner-4.6-R...

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

The Shadowserver

Recorded 22 Apr 2025

Independent exploitation attestation added to the KEV Intelligence record.

Proof of concept available

GitHub

Recorded 05 Mar 2021

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

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Source	Added
The Shadowserver First	2025-04-22 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets: 0
User-Agents: 0

Raw values available in Pro and Enterprise.

Scanner coverage

Metasploit template detected 28 Apr 2025.

View Metasploit template

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner	Reference	Detected
Metasploit	https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/http/vmware_view_planner_4_6_uploadlog_rce.rb	28 Apr 2025
Nuclei	https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-21978.yaml	25 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.8 Critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

99.0%

Weaknesses

Improper Input Validation CWE-20 Missing Authorization CWE-862

All CVSS Scores

CVSS v3.1 9.8 Critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2.0 7.5 High

AV:N/AC:L/Au:N/C:P/I:P/A:P

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

GreyOrder/CVE-2021-21978

github · Created 2021-03-05 03:58:33 UTC · 23 stars · AI assessment 90%

CVE-2021-21978 exp

VMware View Planner <4.6 SP1- Remote Code Execution

nuclei · Created Unknown

vmware_view_planner_4_6_uploadlog_rce

metasploit · Created Unknown

Metasploit module for CVE-2021-21978

Timeline

From disclosure to observed exploitation

28 Apr 2025
Metasploit module available

Exploit module available
25 Apr 2025
Nuclei template available

Scanner coverage available
22 Apr 2025
Added to KEV Intelligence KEV Feed

High-confidence, third-party attested exploitation
05 Mar 2021
Public PoC available

Public proof-of-concept code published
03 Mar 2021
CVE published

Vulnerability disclosed publicly
04 Jan 2021
CVE ID reserved

Identifier reserved by the CNA

Pro API

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Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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Evidence confidence and provenance
First-party sensor telemetry
PoC and scanner references
Affected versions and enrichment
Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2021-21978

Free JSON includes basic KEV fields

{
  "cve_id": "CVE-2021-21978",
  "confidence": "High",
  "cvss_score": 9.8,
  "cvss_estimated": false,
  "epss_score": 0.99005,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

Early warning alerts

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