org.json.JSONException

[nancheal]

org.json.JSONException: A JSONObject text must end with '}' at 32021 [character 9 line 914]
at org.json.JSONTokener.syntaxError(JSONTokener.java:451)
at org.json.JSONObject.(JSONObject.java:201)
at org.json.JSONTokener.nextValue(JSONTokener.java:380)
at org.json.JSONObject.(JSONObject.java:215)
at org.json.JSONTokener.nextValue(JSONTokener.java:380)
at org.json.JSONObject.(JSONObject.java:215)
at org.json.JSONObject.(JSONObject.java:319)
at burp.HttpClient.parseResponse(HttpClient.java:51)
at burp.HttpClient.get(HttpClient.java:43)
at burp.VulnersService.loadRules(VulnersService.java:133)
at burp.BurpExtender.initPassiveScan(BurpExtender.java:41)
at com.codemagi.burp.PassiveScan.initialize(PassiveScan.java:37)
at com.codemagi.burp.BaseExtender.registerExtenderCallbacks(BaseExtender.java:49)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at burp.gsu.lambda$registerExtenderCallbacks$0(Unknown Source)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.base/java.lang.Thread.run(Unknown Source)

[elCoderCP4H]

Try changing line 33 from if (burpExtender.getApiKey() != null)
to if (burpExtender.getApiKey() != null && !burpExtender.getApiKey().isEmpty())
in src/main/java/burp/HttpClient.java file.

Then move or delete burp-vulners-scanner-1.2.jar from target folder.
then do 'mvn package'

After compiling you should have a new burp-vulners-scanner-1.2.jar in the target folder.
Install that one into burp :)
hope this works for you.