When Java source code is compiled, it is converted into bytecode, saved in one or more class files, and executed by the Java Virtual Machine (JVM). Java class files may be compiled on one machine and executed on another machine. A properly - generated class file is said to be conforming. When the JVM loads a class file, it has no way of knowing whether the class file is conforming. The class file could have been created by some other process, or an attacker could tamper with a conforming class file.
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ENV04-EX0: On Java 2 systems, the primordial class loader is permitted to omit bytecode verification of classes loaded from the boot class path. These system classes are protected through platform and file system protections , rather than by the bytecode verification process.
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<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="39a5e3ecff6d2ef9-8c24851b-4f694444-bdcbbbf9-9e66d6def54dfec3aae04d2f"><ac:plain-text-body><![CDATA[ | [[Oaks 2001 | AA. Bibliography#Oaks 01]] | The Bytecode Verifier | ]]></ac:plain-text-body></ac:structured-macro> |
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="ed332c5db2357b6a-cf8e9ff6-4e1b4f7b-9ca2baae-14930b2b536ea2ba2ae8ec43"><ac:plain-text-body><![CDATA[ | [[Pistoia 2004 | AA. Bibliography#Pistoia 04]] | Section 7.3, The Class File Verifier | ]]></ac:plain-text-body></ac:structured-macro> |
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