# CVE-2021-22017: VMware vCenter Server Improper Access Control

> CVE-2021-22017: VMware vCenter Server Improper Access Control. CVSS 5.3 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2021-22017
Last updated: 2025-10-21T23:25:31Z

- Published: 2021-09-23 12:13 UTC · Updated: 2025-10-21 23:25 UTC · Assigner: vmware
- CVSS: 5.3 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- EPSS: 49.2%, 99th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2022-01-10, federal due date 2022-01-24, ransomware use: Unknown

## Description

Rhttproxy as used in vCenter Server contains a vulnerability due to improper implementation of URI normalization. A malicious actor with network access to port 443 on vCenter Server may exploit this issue to bypass proxy leading to internal endpoints being accessed.

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- n/a: VMware vCenter Server, VMware Cloud Foundation

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-22017)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2021-22017)
- [https://www.vmware.com/security/advisories/VMSA-2021-0020.html](https://www.vmware.com/security/advisories/VMSA-2021-0020.html)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2021-22017 · Markdown: https://rewindex.com/cve/CVE-2021-22017.md · JSON: https://rewindex.com/api/v1/cves/CVE-2021-22017 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:46:48.742Z