# CVE-2021-21973: VMware vCenter Server and Cloud Foundation Server Side Request Forgery (SSRF)

> A malicious actor with network access can exploit an SSRF vulnerability in the vSphere Client to disclose sensitive information from the vCenter Server.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Yes, since 7 Mar 2022 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Feb 2021
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-5j6h-79mj-qfq2

## What is CVE-2021-21973?

CVE-2021-21973 is a medium-severity server-side request forgery 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 an SSRF (Server Side Request Forgery) vulnerability due to improper validation of URLs in a vCenter Server plugin. A malicious actor with network access to port 443 may exploit this issue by sending a POST request to vCenter Server plugin leading to information disclosure. 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-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2021-21973?

It affects 2 products.


Products: Vmware Cloud Foundation, Vmware Vcenter Server.

## How do I fix CVE-2021-21973?

No fix has been published for CVE-2021-21973 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 21 Mar 2022.

## Is CVE-2021-21973 being exploited?

Yes. Attackers have exploited CVE-2021-21973 in the wild since at least 7 Mar 2022.

Public exploit code:

- automate me! (github_poc): https://github.com/freakanonymous/CVE-2021-21973-Automateme
- VMware vSphere - Server-Side Request Forgery (nuclei): http/cves/2021/CVE-2021-21973.yaml

## 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-2021-21973 and fix it if it is affected.

What it is: CVE-2021-21973 is a medium-severity server-side request forgery 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-2021-21973 in the wild since at least 7 Mar 2022.

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-2021-21973/ (Markdown: https://insights.sbomify.com/CVE-2021-21973/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-21973
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-21973
- OSV: https://osv.dev/vulnerability/CVE-2021-21973

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-21973/
Summaries are generated and may contain mistakes; the official description above is the record.