my(@records, $ref);
while(<DATA>) {
    chomp;
    if(my @fields = /^(\S+): \[(.+?)\] \[(.+?)\] \[(.+?)\] \[(.+?)\]\s*$/) {
        my %record;
        @record{'ticket#', qw(customer status priority owner)} = @fields;
        push @records, $ref = \%record;
    } elsif(s/^\s+//) {
        if(defined $ref->{summary}) {
            $ref->{summary} .= "\n$_";
        } else {
            $ref->{summary} = $_;
        }
    } else {
        warn "Oops: no match in: $_\n";
    }
}

use Data::Dumper;
print Dumper \@records;

__DATA__
fabx-t160: [ggurudut] [UNAN/OWNR] [C2] [kelrod]
   navicli chglun -l 3 -name "newname" doesn't work
fabx-t161: [dozone] [UNAN/OWNR] [C2] [dchoi]
   The GUI needs to hide the CPP SEs from the unimported list
fabx-t162: [haurora] [UNAN/OWNR] [C1] [glade]
   Cisco hardware related bug :idprom error on cisco switch on loading 0.1.5.5
   salagent
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