for me it looks like a typical moisture damage.
Yes, but...
in the first year after the paving was done, the pavement mistakenly had a slope towards the house. Consequently, water stood against the wall here during heavy rain. This was changed afterwards and is no longer the case.
Therefore moisture damage, but it is old.
a dimpled membrane has already been installed.
That is also okay. Therefore I stick to my opinion. Brush off and repaint. If the problem occurs again and it is not due to the incorrect slope, you will probably have to lift the pavement, dig a little and check whether and how the sealing on the wall or on the plaster below ground level looks like.