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In this noncompliant example, security manager checks are used within the constructor but are not replicated throughout, specifically, within the readObject and writeObject methods that are used in the serialization-deserialization process. This allows an attacker to maliciously create instances of the class that bypass security manager checks when deserialization is performed.
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The compliant solution correctly implements security manager checks in all constructors, methods that can modify internal state and methods that retrieve internal state. As a result, an attacker cannot create an instance of the object with modified state (using deserialization) and cannot simply or read the serialized byte stream to uncover sensitive data (using serialization).
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