A moisture-curable, silane-modified oil is disclosed. The silane-modified oil includes an unsaturated oil having at least one unsaturated aliphatic hydrocarbon chain per molecule of the unsaturated oil, and at least one hydrolysable silyl group grafted to the unsaturated aliphatic hydrocarbon chain. The silane-modified oil has a degree of unsaturation that is substantially similar that of the unsaturated oil. A process for forming the moisture-curable, silane-modified oil according to the disclosure includes reacting the unsaturated oil with an unsaturated hydrolysable silane in the presence of a free radical initiator. Also disclosed is a cured silane-modified oil which includes the reaction product of the silane-modified oil and water. Compositions according to the disclosure have relatively low viscosities (facilitating their application to a substrate) and have relatively high levels of silane grafting (resulting in non-leaching cured compositions with a high gel content).