In Eclipse OpenJ9 version 0.8, users other than the process owner may be able to use Java Attach API to connect to an Eclipse OpenJ9 or IBM JVM on the same machine and use Attach API operations, which includes the ability to execute untrusted native code. Attach API is enabled by default on Windows, Linux and AIX JVMs and can be disabled using the command line option -Dcom.ibm.tools.attach.enable=no.
The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Openj9 | Eclipse | 0.8 (including) | 0.8 (including) |
It is often convenient to serialize objects for communication or to save them for later use. However, deserialized data or code can often be modified without using the provided accessor functions if it does not use cryptography to protect itself. Furthermore, any cryptography would still be client-side security – which is a dangerous security assumption. Data that is untrusted can not be trusted to be well-formed. When developers place no restrictions on “gadget chains,” or series of instances and method invocations that can self-execute during the deserialization process (i.e., before the object is returned to the caller), it is sometimes possible for attackers to leverage them to perform unauthorized actions, like generating a shell.