Hassan bin Ibrahim said, concerning a woman who has wealth and asks her husband's permission for Hajj but he does not permit her: Ibrahim al-Sa'igh said: Nafi' said: Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrated that the Messenger of Allah (peace and blessings be upon him) said: "It is not for her to set out except with her husband's permission, and it is not lawful for a woman to travel three nights unless there is with her a mahram who is forbidden to her (that is, one whom she can never marry)."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10126