===== Users can see other customers' cart on a multi-site setup ===== 
On a multi-site Magento store setup on a cPanel server, carts are being cached and users can see the cart of other customers.

User virtual host cache root should be under /home/$USER and can not be in a centralized location. Please refer to [[litespeed_wiki:cache:common_installation:cpanel-shared| this wiki]] for cPanel environment cache root setup.

Once the correct cache root is set and purge the cache, problem resolved.