Apparently. The Soviets got Aldrich Ames of course, but they lost much of their intelligence assets in the Red Scare because recruiting became harder and much more costly. They had some in the State Dept during WWII, the Rosenbergs of course, but as a single operation they never got near the level of the CoS. The Walker Spy Ring maybe, was much more important, but as a rule intelligence agencies work very small scale, with as few links as possible between agents and officers to stop leaks.