/usr/lib/cruft/explain/munin is in cruft-common 0.9.25.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 | #!/bin/dash
for file in $(ls /usr/share/munin/plugins);
do
[ -e /etc/munin/plugins/$file ] && echo /etc/munin/plugins/$file
done
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