Since upgrading to Wildfly (Hibernate 4.3.7) we are experiencing problems persisting certain entities to an Oracle database.
The entity contains an attribute of type java.lang.Serializable and is mapped to an Oracle BLOB column.
When the value of the Serializable attribute is a byte[] then this is not properly serialized to the database.
The value stored does not correspond to the Java Object Serialization Specification, instead the exact contents of the byte array are saved, without the usual header information associated with Java Object Serialization.

When we try to read this back from the database into our entity we get the exception shown below, so basically Hibernate cannot read what it wrote.

We have attached a test case to demonstrate this problem.

Caused by: org.hibernate.type.SerializationException: could not deserialize
at org.hibernate.internal.util.SerializationHelper.doDeserialize(SerializationHelper.java:262) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.util.SerializationHelper.deserialize(SerializationHelper.java:306) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.descriptor.java.SerializableTypeDescriptor.fromBytes(SerializableTypeDescriptor.java:155) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.descriptor.java.SerializableTypeDescriptor.wrap(SerializableTypeDescriptor.java:130) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.descriptor.java.SerializableTypeDescriptor.wrap(SerializableTypeDescriptor.java:44) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.descriptor.sql.VarbinaryTypeDescriptor$2.doExtract(VarbinaryTypeDescriptor.java:71) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.descriptor.sql.BasicExtractor.extract(BasicExtractor.java:64) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:267) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:263) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:253) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.type.AbstractStandardBasicType.hydrate(AbstractStandardBasicType.java:338) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:2969) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.plan.exec.process.internal.EntityReferenceInitializerImpl.loadFromResultSet(EntityReferenceInitializerImpl.java:324) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.plan.exec.process.internal.EntityReferenceInitializerImpl.hydrateEntityState(EntityReferenceInitializerImpl.java:251) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.readRow(AbstractRowReader.java:107) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.plan.exec.internal.EntityLoadQueryDetails$EntityLoaderRowReader.readRow(EntityLoadQueryDetails.java:255) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.plan.exec.process.internal.ResultSetProcessorImpl.extractResults(ResultSetProcessorImpl.java:129) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:138) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:102) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.entity.plan.AbstractLoadPlanBasedEntityLoader.load(AbstractLoadPlanBasedEntityLoader.java:186) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.loader.entity.plan.LegacyBatchingEntityLoaderBuilder$LegacyBatchingEntityLoader.load(LegacyBatchingEntityLoaderBuilder.java:130) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:4126) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:503) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:468) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:213) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:275) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:151) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1070) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.access$2000(SessionImpl.java:176) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl$IdentifierLoadAccessImpl.load(SessionImpl.java:2551) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.get(SessionImpl.java:955) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.find(AbstractEntityManagerImpl.java:1110) [hibernate-entitymanager-4.3.7.Final.jar:4.3.7.Final]
... 183 more
Caused by: java.io.StreamCorruptedException: invalid stream header: 63726561
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:804) [rt.jar:1.7.0_71]
at java.io.ObjectInputStream.<init>(ObjectInputStream.java:299) [rt.jar:1.7.0_71]
at org.hibernate.internal.util.SerializationHelper$CustomObjectInputStream.<init>(SerializationHelper.java:328) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.util.SerializationHelper$CustomObjectInputStream.<init>(SerializationHelper.java:318) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.util.SerializationHelper.doDeserialize(SerializationHelper.java:237) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
... 214 more