Open source software (OSS) has reshaped and remodeled various layers of the organizational ecosystem, becoming an important strategic asset for enterprises. Still, many enterprises are reluctant to adopt OSS. Knowledge about technological risks and their importance for IT executives is still under researched. We aim to identify the technological risks and their importance for OSS adoption during the risk identification phase in the enterprise context. We conducted an extensive literature review, identifying 34 risk factors from 88 papers, followed by an online survey of 115 IT executives to study the risk factors' importance. Our results will be very valuable for practitioners to use when evaluating, assessing and calculating the risks related to OSS product adoption. Also, researchers can use it as a base for future studies to expand current theoretical understanding of the OSS phenomenon related to IT risk management.