searching a mjpeg stream url including credentials for newer firmwares

Well, it might work, but I think it’s not the best/smartest way. With onvif you could do a lot more than getting a snapshot. Disabling the authentication opens the cam to everyone who gains access to your network, no matter which way
My cam is behind my NVR, which would open a lot more access by disabling onvif authentication for the whole NVR.
 
I know what you mean :) but also ONVIF Auth. function is “disable” by default.
 
I'll send an email to AVM and ask about the digist auth.
Answer from AVM:

ich habe soeben Rückmeldung zu Ihrer Problematik erhalten. Aktuell wird nur Basic unterstützt. Die Unterstützung von Digest und ggf. auch SSL ist über kommende Updates in Planung

So only basic auth. (at the moment).
 
To download a certain part of the recording from a NVR, Can you try:

HTML:
http://User:password@NVR_IP/cgi-bin/loadfile.cgi?action=startLoad&channel=<ChannelNo>&startTime=<starttime>&endTime=<endtime>[&subtype=<typeNo>]