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Potential attacks
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Recursive call
Recursive calling vulnerability or race to empty is is the kind of attack seen on Friday 2016-06-17. Here is what happens:
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The process is draining the ether contained in the DAO into a child DAO.
The dao exploit followed this pattern: propose a split. Execute the split. When the DAO goes to withdraw your reward, call the function to execute a split before that withdrawal finishes. The source code, TokenCreation.sol, transfers tokens from the parent DAO to the child DAO. Basically the attacker is using this to transfer more tokens than they should be able to into their child DAO.
In essence, a call that looks like a regular call can easily be turned into a recursive call, and unless the application is coded very carefully, it can be used to make multiple withdrawals when only one should be allowed.
Callstack depth limit
Send with throw
Race to empty
Unchecked send
Re-entrancy
Loss of state
Copycat
Solutions
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Soft fork
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