CVE-2021-21972: VMware vCenter Server Remote Code Execution Vulnerability

Vulnerability summary

CVE-2021-21972 is a high (CVSS 10.0) Path Traversal vulnerability in VMware vCenter Server. It is known to be exploited: CISA lists it, first on 03-11-2021. It has been used in ransomware campaigns. EPSS estimates a 99.87% chance of exploitation in the next 30 days, higher than 99.9% of scored vulnerabilities. 6 public exploits are recorded.

Timeline

1. 24-02-2021
   PublishedVulnerability first disclosed.
2. 03-11-2021
   Added to CISA KEVVMware vCenter Server Remote Code Execution Vulnerability
3. 17-11-2021
   CISA remediation dueApply updates per vendor instructions.
4. 12-08-2026
   Last modifiedVulnerability information updated.

Description

The vSphere Client (HTML5) contains a remote code execution vulnerability in a vCenter Server plugin. A malicious actor with network access to port 443 may exploit this issue to execute commands with unrestricted privileges on the underlying operating system that hosts vCenter Server. This affects VMware vCenter Server (7.x before 7.0 U1c, 6.7 before 6.7 U3l and 6.5 before 6.5 U3n) and VMware Cloud Foundation (4.x before 4.2 and 3.x before 3.10.1.2).

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.