Abu'l-'Ubaydayn said, "I asked 'Abdullah about those who squander and he said, 'They are those who spend incorrectly.'"  

عَنْ أَبِي الْعُبَيْدَيْنِ قَالَ سَأَلْتُ عَبْدَ اللهِ عَنِ الْمُبَذِّرِينَ قَالَ الَّذِينَ يُنْفِقُونَ فِي غَيْرِ حَقٍّ  

Ibn 'Abbas said that he said that "the squanderers" were those who wasted money incorrectly.  

عَنِ ابْنِ عَبَّاسٍ {الْمُبَذِّرِينَ} قَالَ الْمُبَذِّرِينَ فِي غَيْرِ حَقٍّ