And here is a Pravda article mentioning the alarm that occurred in Sweden when they found out that the Russians had better maps of Sweden than they did, and allegations that a lot of the data was gathered by KGB agents posing as the children of Swedish Communists who moved to the USSR in the 1930s and then disappeared in Stalin's purges.
Didn't the German Wehrmacht during WWII find out that the publically-available Soviet maps of the USSR were wildly and deliberately inaccurate?
Actually, the Soviet Union went to great efforts producing extremely accurate maps of the entire world except the Soviet Union. Maps of the USSR were deliberately mangled in order to confuse foreign spies and the rest of the local population.
And I'm talking about the 1980s here. Remember that Stalin was orders of magnitude more paranoid than recent Soviet leaders.
In Afghanistan, the best maps we could get ahold of were soviet. We could even see the buildings that became our compound. The detail was exqusite and far better than anything I ever used in the Oz military. Of course, the names where in Russian and they used the unique Russian grid system, but compared to the crappy UN maps they were a godsend. We even found villages on them that the UN claimed didn't exist (and therefore weren't included in food distributions - something that is repeating itself in Niger today). How did we get ahold of these maps (on CD)? A guy from another French NGO got drunk with some British SAS guys in Kabul and they slipped him a copy...