Merge pull request from GHSA-m87f-39q9-6f55

notebook/log.py

@@ -44,11 +44,15 @@ def log_request(handler, log=access_log, log_json=False):
         ns['referer'] = request.headers.get('Referer', 'None')
         msg = msg + ' referer={referer}'
     if status >= 500 and status != 502:
-        # log all headers if it caused an error
+        # Log a subset of the headers if it caused an error.
+        headers = {}
+        for header in ['Host', 'Accept', 'Referer', 'User-Agent']:
+            if header in request.headers:
+                headers[header] = request.headers[header]
         if log_json:
-            log_method("", extra=dict(props=dict(request.headers)))
+            log_method("", extra=dict(props=headers))
         else:
-            log_method(json.dumps(dict(request.headers), indent=2))
+            log_method(json.dumps(dict(headers), indent=2))
     if log_json:
         log_method("", extra=dict(props=ns))
     else: