dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 3 May 2022.
Vcenter ServerApplication · VMware

CVE-2020-3952

CRITICAL · 9.8 CVSS v3.1 Published 2020-04-10
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
In the wild High EPSS Public exploit Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Under certain conditions, vmdir that ships with VMware vCenter Server, as part of an embedded or external Platform Services Controller (PSC), does not correctly implement access controls.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

This is a critical access control vulnerability in VMware's vmdir (VMware Directory Service) component that ships with vCenter Server and Platform Services Controller. Under certain conditions, the service fails to correctly implement access controls, potentially allowing unauthorized access to sensitive authentication and authorization functions within the VMware environment.

MitigationApply the VMware security patch for CVE-2020-3952 immediately. Prior to patching, ensure proper network segmentation and restrict access to the PSC/vCenter management interfaces to limit exposure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Vcenter ServerApplication
Affected:= 6.7

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify vCenter Server version
    Log into the vSphere Client and navigate to Administration > About, or run 'vmware -v' via SSH/console on the vCenter Server Appliance (VCSA). Alternatively, check /etc/vmware-vpx/release or query the vCenter MOB at https://<vcenter>/mob/ under the about property.
    Affected if The installed version is exactly 6.7 (any build of 6.7 series)
  2. Determine PSC deployment type
    Check if vCenter Server uses embedded PSC or external PSC. On VCSA, run 'vpxd -l' or inspect /var/lib/vmware/vpxd/vcdb.properties. In the vSphere Client, go to Administration > Deployment > System Configuration to see if PSC is listed separately.
    Affected if The deployment uses either embedded PSC or external PSC (both are affected by this CVE)
  3. Verify vmdir service status
    On the VCSA or PSC node, run 'vmdir --version' or check service status via 'systemctl status vmdir' or 'service vmdir status'. The vmdir service is the VMware Directory Service component.
    Affected if vmdir service is running and responding (the vulnerability exists in this component)
  4. Check vmdir access controls
    Review vmdir configuration and ACL settings in the directory service. Query the LDAP port (typically 389 or 636 for LDAPS) on the PSC or embedded PSC using ldapsearch or a similar tool to inspect permissions on cn=Administrator,cn=Users and other sensitive OUs.
    Affected if Unauthenticated or low-privilege queries return sensitive administrative group memberships or user attributes they should not access

You are affected if vCenter Server is exactly version 6.7 and uses either embedded or external PSC with vmdir service running.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the VMware security patch for CVE-2020-3952 immediately. Prior to patching, ensure proper network segmentation and restrict access to the PSC/vCenter management interfaces to limit exposure.

Recommended fix Moderate confidence

vCenter Server 6.7 Update 3f (6.7.0.30000) or later

  1. 1. Backup the vCenter Server Appliance (VCSA) before making any changes
  2. 2. Download the latest vCenter Server 6.7 update from the VMware Customer Connect portal
  3. 3. Upload the update to the vCenter Server and run the update command: 'software-packages install --url <update-file>'
  4. 4. Alternatively, use the vCenter Server Management interface (VAMI) at https://<vcsa-hostname>:5480 to apply the update
  5. 5. After the update completes, verify the vmdir service is running correctly
  6. 6. Confirm the version shows 6.7.0u3f or later which contains the security fix for CVE-2020-3952
Caveat Standard vCenter update - minimal risk; ensure sufficient downtime window for the upgrade

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Vcenter Server Exploited in the wild — priority engagement
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,120.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-3952 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-3952 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data