VMware vCenter Server Could Allow for Remote Code Execution

by | May 26, 2021 | Advisories

Multiple vulnerabilities have been discovered in VMware vCenter Server, the most severe of which could allow for remote code execution. VMware vCenter Server is a centralized management utility for VMware, and is used to manage virtual machines, multiple ESXi hosts, and all dependent components from a single centralized location. Successful exploitation of these vulnerabilities could allow an attacker to execute remote code in context of the user running the application.

THREAT INTELLIGENCE: There are currently no reports of these vulnerabilities being exploited in the wild.

SYSTEMS AFFECTED:

  • VMware vCenter Server versions 6.5, 6.7, 7.0

RISK:

Government:

  • Large and medium government entities: High
  • Small government: Medium

Businesses:

  • Large and medium business entities: High
  • Small business entities: Medium

Home users: Low

TECHNICAL SUMMARY:

Multiple vulnerabilities have been discovered in VMware vCenter Server, which could result in remote code execution. Details of these vulnerabilities are as follows:

  • A remote code execution vulnerability in vCenter Server which enables a malicious actor to execute commands with unrestricted privileges. (CVE-2021-21985)
  • An authentication mechanism issue in vCenter Server Plug-ins which enable a malicious actor to perform unauthorized actions. (CVE-2021-21086)

Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights. A pre-requisite of exploiting these vulnerabilities is that the malicious actor must have network access over port 443 to exploit these vulnerabilities. Successful exploitation of these vulnerabilities could allow an attacker to execute arbitrary code in context of the user running the application.

RECOMMENDATIONS:

We recommend the following actions be taken:

  • Apply appropriate updates provided by VMware to vulnerable systems immediately after appropriate testing.
  • Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments especially from un-trusted sources.
  • Apply the Principle of Least Privilege to all systems and services.

REFERENCES:

VMware:

https://www.vmware.com/security/advisories/VMSA-2021-0010.html

CVE:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21985

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21986