CVE-2021-21973

KEVVMware vCenter Server and Cloud Foundation Server Side Request Forgery (SSRF) Vulnerability

Description

VMware vCenter Server and Cloud Foundation Server contain a SSRF vulnerability due to improper validation of URLs in a vCenter Server plugin. This allows for information disclosure.

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).

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

PublishedFeb 24, 2021

Last modifiedJun 17, 2026

Added to KEVMar 7, 2022

Remediation dueMar 21, 2022

References

vmware.com/security/advisories/VMSA-2021-0002.htmlVendor Advisory
cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21973US Government Resource

0 recent articles mention this CVE

Risk assessment · High

Actively exploited. Patch immediately.

Exploitation: Confirmed in the wild (CISA KEV)
Federal remediation deadline: Overdue by 1680 days
CVSS: 5.3 MEDIUM
EPSS (30-day exploit probability): 88.0% · top 1% of all CVEs
Weakness: CWE-918
Attack vector: Network, remotely reachable
Preconditions: No privileges and no user interaction

Recommended actions

1.Apply updates per vendor instructions.
2.Treat as emergency change: patch or isolate internet-facing instances first.
3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.

Assessment is derived automatically from the live signals above; verify against your own asset inventory.