Noone can steal coins, it just makes it seem like the coins aren't there, but a rescan should fix that.
Regardless the issue doesn't affect code base 0.8.5 its 0.8.6 where users are reporting seeing the issue.
a rescan does not fix the issue. the issue affects all bitcoin versions. you are right that it doesn't result in stealing coins. it does result in incorrect balance reports and the inability to spend coins.