Wiktionary
external risk
n. 1 (context insurance English) Risks that are produced by a non-human source and are beyond human control. They are unexpected but happen regularly enough in a general population to be broadly predictable. Good examples of external risks are natural disasters such as earthquakes and volcanoes. 2 (context project management English) Risks that are external to the project and the project manager can not control. Good examples of external risks are changes in government legislation, changes in strategy from senior managers, and the economy.
Wikipedia
External risk
External Risks are generally something that is uncontrollable by the first party.