What is the authenticity of the hadith: "All sins—Allah postpones whatsoever He wills of them until the Day of Resurrection, except for oppression, disobedience to parents, or cutting off ties of kinship, for which He hastens (the punishment) for its perpetrator in this world before death"?

The hadith mentioned by the questioner is authentic. It was narrated by Al-Bukhari in "Al-Adab Al-Mufrad" with the same wording, and Al-Albani authenticated it. It was also narrated with another wording: "There is no sin more deserving that its punishment be hastened for its perpetrator, in addition to what is stored for him [in the Hereafter], than injustice and cutting off ties of kinship." And it was reported by Al-Hakim and others with the wording: "Two doors whose punishment is hastened in this world: injustice and disobedience to parents."