CVE-2021-21986
9.8
CRITICAL · CVSS 3.1 · EPSS 13.3% (pctl 96)
Patch early
EPSS 13.3% — above the 10% action threshold.
Description
The vSphere Client (HTML5) contains a vulnerability in a vSphere authentication mechanism for the Virtual SAN Health Check, Site Recovery, vSphere Lifecycle Manager, and VMware Cloud Director Availability plug-ins. A malicious actor with network access to port 443 on vCenter Server may perform actions allowed by the impacted plug-ins without authentication.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 13.27% — more likely to be exploited than 96% of all CVEs |
| Weakness | CWE-306 |
| On CISA KEV | no |
| Public exploit | none known |
| Published | 2021-05-26 |
| Last modified | 2026-06-17 |
Affected (2)
| Vendor | Product |
|---|---|
| vmware | cloud foundation |
| vmware | vcenter server |
References
→ the Explorer · watch your stack · NVD