Vulnerability Database

383,371

Total vulnerabilities in the database

CVE-2021-21972 — vmware / cloud_foundation

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

The vSphere Client (HTML5) contains a remote code execution vulnerability in a vCenter Server plugin. 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. 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).

  • Published: Feb 24, 2021
  • Updated: Sep 10, 2026
  • CVE: CVE-2021-21972
  • Severity: Critical
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Critical
  • Score: 9.8
  • AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2:

  • Severity: High
  • Score: 10
  • AV:N/AC:L/Au:N/C:C/I:C/A:C
Software Affected versions
vmware / cloud_foundation >= 3.0, < 3.10.1.2
vmware / cloud_foundation >= 4.0, < 4.2
vmware / vcenter_server = 6.5
vmware / vcenter_server = 6.5-a
vmware / vcenter_server = 6.5-b
vmware / vcenter_server = 6.5-c
vmware / vcenter_server = 6.5-d
vmware / vcenter_server = 6.5-e
vmware / vcenter_server = 6.5-f
vmware / vcenter_server = 6.5-update1d
vmware / vcenter_server = 6.5-update1e
vmware / vcenter_server = 6.5-update1g
vmware / vcenter_server = 6.5-update2
vmware / vcenter_server = 6.5-update2b
vmware / vcenter_server = 6.5-update2c
vmware / vcenter_server = 6.5-update2d
vmware / vcenter_server = 6.5-update2g
vmware / vcenter_server = 6.5-update3
vmware / vcenter_server = 6.5-update3d
vmware / vcenter_server = 6.5-update3f
vmware / vcenter_server = 6.5-update3k
vmware / vcenter_server = 6.7
vmware / vcenter_server = 6.7-a
vmware / vcenter_server = 6.7-b
vmware / vcenter_server = 6.7-d
vmware / vcenter_server = 6.7-update1
vmware / vcenter_server = 6.7-update1b
vmware / vcenter_server = 6.7-update2
vmware / vcenter_server = 6.7-update2a
vmware / vcenter_server = 6.7-update2c
vmware / vcenter_server = 6.7-update3
vmware / vcenter_server = 6.7-update3a
vmware / vcenter_server = 6.7-update3b
vmware / vcenter_server = 6.7-update3f
vmware / vcenter_server = 6.7-update3g
vmware / vcenter_server = 6.7-update3j
vmware / vcenter_server = 7.0
vmware / vcenter_server = 7.0-a
vmware / vcenter_server = 7.0-b
vmware / vcenter_server = 7.0-c
vmware / vcenter_server = 7.0-d
vmware / vcenter_server = 7.0-update1
vmware / vcenter_server = 7.0-update1a

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.