High severity · published Sep 22, 2021
CVE-2021-21991
The vCenter Server contains a local privilege escalation vulnerability due to the way it handles session tokens
7.8
CVSS
0.3%
EPSS
No
On KEV
Description
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).
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 24% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
VS
vCenter Server · VMware
6.5; 6.5; 6.5; 6.5; 6.5; 6.5; +34 more · source: NVD
CF
Cloud Foundation · Vmware
3.0 before 3.10.2.2; 4.0 before 4.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21991
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21991
Patch
https://www.vmware.com/security/advisories/VMSA-2021-0020.html
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