#VU56791 Permissions, Privileges, and Access Controls in vCenter Server - CVE-2021-21991

Vulnerability identifier: #VU56791

Vulnerability risk: Low

CVSSv4.0: 7.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:U/U:Clear]

CVE-ID: CVE-2021-21991

CWE-ID: CWE-264

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
vCenter Server
Server applications / Virtualization software

Vendor: VMware, Inc

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the way the vCenter Server handles session tokens. A local user can escalate privileges to Administrator on the vSphere Client (HTML5) or vCenter Server vSphere Web Client (FLEX/Flash).

Mitigation
Install updates from vendor's website.

Vulnerable software versions

vCenter Server: 6.5 U1 - 7.0.0

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External links
https://www.vmware.com/security/advisories/VMSA-2021-0020.html

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.