#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11107038
use warnings;

my @lines = <DATA>;
@lines = map /[^=:\s]*,[^=:\s]*/ ? map "$`$_$'", split /,/, $& : $_, @lines
  while "@lines" =~ /,/;
my %hash = split ' ', "@lines";
$_ = { split /[=|]/ } for values %hash;
use Data::Dump 'dd'; dd \%hash;

__DATA__
Prefix1=A,B:c,d value1=5
Prefix2=A:b,c:1,2 value2=6
Prefix4=A:*:1,2 value4a=10|value4b=20
Prefix5,Prefix6=A:*:1,7 value5=10