Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said that the Prophet (peace and blessings be upon him) applied unperfumed oil while he (peace and blessings be upon him) was in ihram.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 9107
Murrah al-Shaybani said: We passed by Abu Dharr (may Allah be pleased with him) while in ihram, and our feet had cracked. He said: "Apply oil to them."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 9108