What is CVE-2021-21991?

CVE-2021-21991 is a high-severity vulnerability in VMware Cloud Foundation. CVSS score: 7.8/10. Published 2021-09-22.

How severe is CVE-2021-21991?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2021-21991 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in VMware Cloud Foundation

CVE-2021-21991

The vCenter Server contains a local privilege escalation vulnerability due to the way it handles session tokens. A malicious actor with non-administrative user access on vCenter Server host may exploit this issue to escalate privileges to Administrator on the vSphere Client (HTML5) or vCenter Server vSphere Web Client (FLEX/Flash).

EPSS: 0.003 (24.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Vmware Cloud_foundation
Vmware Vcenter_server — versions 6.5, 6.7, 7.0
N/a Vmware Vcenter Server, Cloud Foundation — versions VMware vCenter Server(7.x before 7.0 U2c, 6.7 before 6.7 U3o and 6.5 before 6.5 U3q) and VMware Cloud Foundation (4.x before 4.3 and 3.x before 3.10.2.2)

Public proof-of-concept exploits

HynekPetrak/HynekPetrak

References

security@vmware.com (Patch, x_refsource_MISC, Vendor Advisory)

Frequently asked questions

What is CVE-2021-21991?: CVE-2021-21991 is a high-severity vulnerability in VMware Cloud Foundation. CVSS score: 7.8/10. Published 2021-09-22.
How severe is CVE-2021-21991?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-21991 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.