In　a　recent　article　[Gao　et　al.,　Sci.　China-Phys.　Mech.　Astron.　63,　120311　(2020)],　a　two-receiver　measurement-device-independent　quantum　secret　sharing　(MDI-QSS)　protocol　was　presented.　It　was　proven　to　be　secure　against　eavesdropping　and　generalized　to　the　multireceiver　case.　However,　the　participant　attack　is　a　fatal　threat　to　QSS　protocols.　Here,　we　highlight　that　a　dishonest　participant　can　obtain　a　sender＇s　secret　message　alone　without　introducing　any　detectable　error,　evidencing　the　vulnerability　of　the　MDI-QSS　protocol　to　the　participant　attack.