This version closes a security gap when adding attachments to messages, which is why we strongly recommend updating to this version as soon as possible. Up to this version it was possible to upload arbitrary files as attachment to a message which could then be executed if the attachment is stored in the file system. If you have deactivated email messages or saving attachments, you are not affected. Uploading attachments is also only possible for logged-in users.

We recommend you to read our announcements for version 4.3 if you have not done before.

A full list of all new features and bugfixes can be found in our issue tracker for version 4.3 and 4.3.10!
Full Changelog: https://github.com/Admidio/admidio/compare/v4.3.8..v4.3.10

If you are new to Admidio and want to install it on your webpage than the following wikipage could help: Install Admidio

The following wiki pages maybe interesting on an Update: Update Admidio