This hadith has been narrated through a couple of other chains of transmitters, one which says "the similitude of the disbeliever" instead and another which agrees with the wording of the previous hadith.
عَنِ النَّبِيِّ ﷺ غَيْرَ أَنَّ مَحْمُودًا قَالَ فِي رِوَايَتِهِ عَنْ بِشْرٍ وَمَثَلُ الْكَافِرِ كَمَثَلِ الأَرْزَةِ وَأَمَّا ابْنُ حَاتِمٍ فَقَالَ مَثَلُ الْمُنَافِقِ كَمَا قَالَ زُهَيْرٌ