diff --git a/lib/tfw/components/process_managing_event_handler.py b/lib/tfw/components/process_managing_event_handler.py
index 6fcc248..ab63607 100644
--- a/lib/tfw/components/process_managing_event_handler.py
+++ b/lib/tfw/components/process_managing_event_handler.py
@@ -36,6 +36,9 @@ class ProcessManagingEventHandler(TriggerlessEventHandler):
 
     @_with_monitor_paused
     def handle_event(self, key, data_json):
-        data = data_json['data']
-        self.processmanager(data['command'], data['process_name'])
-        self.uplink.send(self.key, {'data': {'process_name': data['process_name']}})
+        try:
+            data = data_json['data']
+            self.processmanager(data['command'], data['process_name'])
+            self.uplink.send(self.key, {'data': {'process_name': data['process_name']}})
+        except KeyError:
+            log.error('IGNORING MESSAGE: Invalid data_json received: {}'.format(data_json))
diff --git a/lib/tfw/components/source_code_event_handler.py b/lib/tfw/components/source_code_event_handler.py
index dd26072..003264a 100644
--- a/lib/tfw/components/source_code_event_handler.py
+++ b/lib/tfw/components/source_code_event_handler.py
@@ -84,10 +84,13 @@ class SourceCodeEventHandler(TriggerlessEventHandler):
         data['files'] = self.filemanager.files
 
     def handle_event(self, key, data_json):
-        data = data_json['data']
-        data_json['data'] = self.commands[data['command']](data)
-        self.attach_fileinfo(data)
-        return data_json
+        try:
+            data = data_json['data']
+            data_json['data'] = self.commands[data['command']](data)
+            self.attach_fileinfo(data)
+            return data_json
+        except KeyError:
+            log.error('IGNORING MESSAGE: Invalid data_json received: {}'.format(data_json))
 
     def cleanup(self):
         self.monitor.stop()
diff --git a/lib/tfw/components/terminado_event_handler.py b/lib/tfw/components/terminado_event_handler.py
index 4a8f98a..649f823 100644
--- a/lib/tfw/components/terminado_event_handler.py
+++ b/lib/tfw/components/terminado_event_handler.py
@@ -23,8 +23,11 @@ class TerminadoEventHandler(TriggerlessEventHandler):
 
     def handle_event(self, key, data_json):
         log.debug('TerminadoEventHandler received event: {}'.format(data_json))
-        data_json['data'] = self.commands[data_json['data']['command']](data_json['data'])
-        return data_json
+        try:
+            data_json['data'] = self.commands[data_json['data']['command']](data_json['data'])
+            return data_json
+        except KeyError:
+            log.error('IGNORING MESSAGE: Invalid data_json received: {}'.format(data_json))
 
     def write(self, data):
         self.terminado_server.pty.write(data['shellcmd'])