{"id":"CVE-2021-21986","aliases":["EUVD-2021-9157","GHSA-6qhw-394j-xwvg"],"status":"published","title":"The vSphere Client (HTML5) contains a vulnerability in a vSphere authentication mechanism for the...","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.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.13265,"percentile":0.96413,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-287","CWE-306"],"published":"2021-05-26T14:04:35Z","modified":"2026-06-17T03:36:30Z","products":[{"vendor":"vmware","product":"cloud_foundation"},{"vendor":"vmware","product":"vcenter_server"}],"references":[{"url":"https://www.vmware.com/security/advisories/VMSA-2021-0010.html","tags":["x_refsource_MISC","x_transferred","Vendor Advisory"]},{"url":"http://packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.html","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","VDB Entry"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-21986"},{"url":"https://github.com/advisories/GHSA-6qhw-394j-xwvg"}],"sources":{"cve":[{"id":"CVE-2021-21986","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.","status":"published","published":"2021-05-26T14:04:35Z","modified":"2024-08-03T18:30:23.588Z","updated_at":"2026-11-02T14:33:00.488332Z"}],"euvd":[{"id":"EUVD-2021-9157","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.","status":"published","published":"2021-05-26T14:04:35Z","modified":"2024-08-03T18:30:23Z","updated_at":"2026-11-03T03:25:04.094929Z"}],"ghsa":[{"id":"GHSA-6qhw-394j-xwvg","title":"The vSphere Client (HTML5) contains a vulnerability in a vSphere authentication mechanism for the...","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.","status":"published","published":"2022-05-24T19:03:21Z","modified":"2023-01-27T05:02:48Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:42:06.500861Z"}],"nvd":[{"id":"CVE-2021-21986","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.","status":"published","published":"2021-05-26T15:15:07.973Z","modified":"2026-06-17T03:36:30.417Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":10,"vector":"AV:N/AC:L/Au:N/C:C/I:C/A:C","level":"high","assessor":"primary"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T14:06:53.987491Z"}]}}