Major world events would be given an official spin but completely obscuring them wasn't seen as realistic and wasn't attempted. More obscure facts might be simply ignored, however. According to Wikipedia, radio jamming commenced in 1948. It was hugely expanded over the coming decades which isolated Soviets from foreign broadcast media.

Paradoxically, Soviet citizens (and foreigners) were probably less informed about events within the USSR itself. There the censors could stifle much news at source, preventing facts from becoming established and easing the task of controlling information.