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Python Extension Loading Errors

Anthony | Last updated: Nov 11, 2023 11:32PM UTC

I'm encountering this issue with all Python extensions from the BApp store and my personal extensions. This started to happen after a burp update at some point. I'm currently running 2023.10.3.4 but this started to happen beforehand. ``` java.lang.ClassCastException: class org.python.core.PySingleton cannot be cast to class burp.IBurpExtender (org.python.core.PySingleton is in unnamed module of loader burp.Zip8 @4ea4a2cf; burp.IBurpExtender is in unnamed module of loader 'app') at burp.Zxa8.Zf(Unknown Source) at burp.Zrvq.ZU(Unknown Source) at burp.Ztgi.ZP(Unknown Source) at burp.Zpc1.lambda$panelLoaded$0(Unknown Source) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:577) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642) at java.base/java.lang.Thread.run(Thread.java:1623) ```

Hannah, PortSwigger Agent | Last updated: Nov 13, 2023 12:06PM UTC

Hi Could you please tell me the version of Jython that you have configured under "Extensions > Extension settings > Python environment"?

Anthony | Last updated: Nov 13, 2023 03:02PM UTC

Hi Hannah, thanks for getting back to me! I've tried with the standalone Jar 2.7.2 and 2.7.3

Hannah, PortSwigger Agent | Last updated: Nov 14, 2023 02:28PM UTC

Thanks for that information. Do you still receive this error with the example "Hello world" extension? - https://github.com/PortSwigger/example-hello-world/blob/master/python/HelloWorld.py I would recommend quickly commenting out line 29, so you don't end up with an expected stack trace in your error output. Please make sure that you do not have any other extensions loaded at the same time, just in case. Do you have any special characters or multi-byte characters present in your file path for either your extension or for the location of your standalone Jython environment?

Anthony | Last updated: Nov 16, 2023 04:17PM UTC

Hi Hannah, I unenabled all extensions and I ran into the same issue. ``` java.lang.ClassCastException: class org.python.core.PySingleton cannot be cast to class burp.IBurpExtender (org.python.core.PySingleton is in unnamed module of loader burp.Zip8 @1fc45654; burp.IBurpExtender is in unnamed module of loader 'app') at burp.Zxa8.Zf(Unknown Source) at burp.Zrvq.ZU(Unknown Source) at burp.Ztgi.ZP(Unknown Source) at burp.Zpc1.lambda$panelLoaded$0(Unknown Source) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:577) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642) at java.base/java.lang.Thread.run(Thread.java:1623) ```

Hannah, PortSwigger Agent | Last updated: Nov 17, 2023 04:07PM UTC