Security checks based on untrusted sources can be bypassed. The untrusted object or parameter should be defensively copied before the security check is performed. The copy operation must be a deep copy; the implementation of the clone() method may produce a shallow copy, which can still be compromised. In addition, the implementation of the clone() method can be provided by the attacker. See guidelines rules VOID MET08-J. Do not use the clone method to copy untrusted method parameters and OBJ14-J. Defensively copy mutable inputs and mutable internal components for more information.
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Note that using the clone() method instead of the openFile() method would copy the attacker's class, which is not desirable. (Refer to guideline rule VOID MET08-J. Do not use the clone method to copy untrusted method parameters.)
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Search for vulnerabilities resulting from the violation of this guideline rule on the CERT website.
Related Guidelines
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