Allopanishad
The author of Allopanishad was a converted Muslim of 16th century. He was from Julaha (weaver) community and a student from Chishtiya Silsila where he got his (faulty) knowledge of Sanskrit . He forged the Upanishad anonymously.
The claim that he was a Brahman is false and fraudulent. It was first started by Audrey Truschke