The Messenger of Allah ﷺ said, "A woman must not fast a single day while her husband is present without his permission, except in Ramadan."
حدثنا وكيع عن سفيان عن أبي الزناد عن موسى بن أبي عثمان عن أبيه
قال رسول الله ﷺ لا تصوم المرأة يوما واحدا وزوجها شاهد إلا بإذنه إلا رمضان
Its isnad is sahih. It occurred earlier at hadith no. 7338, and at 2/444, 424 in the printed edition. Musa bin Abu Uthman Tabban is acceptable, and his father is also acceptable, having a hadith in Muslim, while his son was narrated from by Bukhari in a suspended form. Sahih.