Changes to Ionos, SMTP smuggling and Linux Long Term Support Kernel 6.6.12.

Ionos has informed you that they will be making a change to the authentication on the relay server or smarthost from Monday, 29.01.2024. All customers who have registered several mail domains with Ionos and also use several of them for sending must adjust the configuration. This update provides the option to store a separate authentication for each mail domain.

At the CCC congress shortly after Christmas, there was a presentation worth seeing about a way of sending emails with forged sender addresses. The attack was called SMTP smuggling and is prevented with this update.

Further information and details can be found in the Release-Notes of each product.