I really don't understand what you are trying to match ... perhaps you simplified your example too much? At any rate, why not use split? 

use strict;
use warnings;
use Data::Dumper;

my $s = <<'ENDSTR';
aaa       : AAA
bbb       : BBB
ccc       : CCC
ENDSTR


my %hash = map { split( /\s+:\s+/, $_, 2) } split ( /\n/, $s );
print Dumper \%hash;

__END__
$VAR1 = {
          'bbb' => 'BBB',
          'ccc' => 'CCC',
          'aaa' => 'AAA'
        };

[download]

UPDATE:
But simple splitting DOES work here.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: Why multiline regex doesn't work? by jeffa
in thread Why multiline regex doesn't work? by nbd

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