Made by HK CVE-2020-11890: Improper input validations in the usergroup table class could lead to a broken ACL configuration to RCE Link https://developer.joomla.org/security-centre/810-20200402-core-missing-checks-for-the-root-usergroup-in-usergroup-table.html PoC Affected version: Joomla core before 3.9.17 User requirement: Admin account (Not superadmin) Gain access: Create a new Superadmin, then trigger RCE. Remote Code Execution (RCE) in Joomla Run cve202011890.py with your credentials and access link rce: Guide to use docker such as: #Step 1: docker pull hoangkien1020/joomla:3.9.16 #Step 2: docker run -d --rm -it -p 8080:80 hoangkien1020/joomla:3.9.16 #Step 3: Access your domain/IP with port 8080: Inside this image with credentials username: password MySQL: root: root (can access via IP:8080/phpmyadmin) superadmin:1234 (Super Users) admin:1234 (Administrator) hacker:1234 (Manager)