tl;dr Find mspaint.exe in memory, inspect it as raw data in gimp
We're presented with a Win10x64 memory dump, let's start by inspecting current processes using volatility:
volatility --profile Win10x64 -f dump1.raw pslist.
There are 2 particularly interesting lines:
Name PID PPID Thds Hnds Sess Wow64 Start
mspaint.exe 4092 2336 3 0 1 0 2016-04-04 16:13:21
notepad.exe 2012 2336 1 0 1 0 2016-04-04 16:14:49
Both of these programs look like a good place to hide the flag. However, we should've gotten the text from notepad using strings, so we'll start with paint.
volatility -f dump1.raw memdump -p 4092 --dump-dir=dump
Produces a 1.8GB file, not very helpful...
It turns out that gimp handles raw data pretty well, we can select size, algorithm and offset.
We started tweaking those values to get a meaningful image.
After some fun we're surprised with:
