# CVE-2021-21972: VMware vCenter Server Remote Code Execution

> Attackers with network access can exploit a path traversal flaw in the vSphere Client to execute arbitrary commands with unrestricted privileges on the host.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 3 Nov 2021 (CISA KEV), used in ransomware
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Feb 2021
- **Updated:** 12 Aug 2026
- **Also known as:** GHSA-c9cr-34rr-8gpr

## What is CVE-2021-21972?

CVE-2021-21972 is a critical path traversal vulnerability in Vmware Cloud Foundation, published on 24 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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).

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2021-21972?

It affects 2 products.


Products: Vmware Cloud Foundation, Vmware Vcenter Server.

## How do I fix CVE-2021-21972?

No fix has been published for CVE-2021-21972 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 17 Nov 2021.

## Is CVE-2021-21972 being exploited?

Yes. Attackers have exploited CVE-2021-21972 in the wild since at least 3 Nov 2021, including in ransomware campaigns.

Public exploit code:

- 一款针对Vcenter的综合利用工具，包含目前最主流的CVE-2021-21972、CVE-2021-21985以及CVE-2021-22005、One Access的CVE-2022-22954、CVE-2022-22972/31656以及log4j，提供一键上传webshell，命令执行或者上传公钥使用SSH免密连接 (github_poc): https://github.com/Schira4396/VcenterKiller
- CVE-2021-21972 Exploit (github_poc): https://github.com/NS-Sp4ce/CVE-2021-21972
- Proof of Concept Exploit for vCenter CVE-2021-21972 (github_poc): https://github.com/horizon3ai/CVE-2021-21972
- NSE scripts to detect CVE-2020-1350 SIGRED and CVE-2020-0796 SMBGHOST, CVE-2021-21972, proxyshell, CVE-2021-34473 (github_poc): https://github.com/psc4re/NSE-scripts
- https://github.com/QmF0c3UK/CVE-2021-21972-vCenter-6.5-7.0-RCE-POC (github_poc): https://github.com/QmF0c3UK/CVE-2021-21972-vCenter-6.5-7.0-RCE-POC
- https://github.com/alt3kx/CVE-2021-21972 (github_poc): https://github.com/alt3kx/CVE-2021-21972

## Other vulnerabilities in Vmware Cloud Foundation

- [CVE-2024-38812](https://insights.sbomify.com/CVE-2024-38812/): VMware vCenter Server Heap-Based Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2024-37079](https://insights.sbomify.com/CVE-2024-37079/): Broadcom VMware vCenter Server Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2022-22954](https://insights.sbomify.com/CVE-2022-22954/): VMware Workspace ONE Access and Identity Manager Server-Side Template Injection (critical 9.8, exploited in the wild)
- [CVE-2021-22005](https://insights.sbomify.com/CVE-2021-22005/): VMware vCenter Server File Upload (critical 9.8, exploited in the wild)
- [CVE-2021-21985](https://insights.sbomify.com/CVE-2021-21985/): VMware vCenter Server Improper Input Validation (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-21972 and fix it if it is affected.

What it is: CVE-2021-21972 is a critical path traversal vulnerability in Vmware Cloud Foundation, published on 24 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2021-21972 in the wild since at least 3 Nov 2021, including in ransomware campaigns.

Affected product: Vmware Cloud Foundation. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2021-21972/ (Markdown: https://insights.sbomify.com/CVE-2021-21972/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-21972
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-21972
- OSV: https://osv.dev/vulnerability/CVE-2021-21972

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-21972/
Summaries are generated and may contain mistakes; the official description above is the record.