Yahya bin Ma'in (may Allah have mercy on him) used to consider the hadith of Sayyiduna al-Miqdam (may Allah be pleased with him) invalid, namely: "The maternal uncle is the heir of one who has no heir." He said: There is no strong hadith on this.
It has also been narrated through another route that is weaker than that.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الفرائض / 12212