Fix html escape

diff --git a/starlette/middleware/errors.py b/starlette/middleware/errors.py
index 9c9005c28ed40c1b83a822f57cbadf4cbc78ff14..1f2c40b4482277ba13299589f009eca3b5a09b58 100644 (file)
--- a/starlette/middleware/errors.py
+++ b/starlette/middleware/errors.py
@@ -1,3 +1,4 @@
+import html
 import asyncio
 import inspect
 import traceback
@@ -221,7 +222,7 @@ class ServerErrorMiddleware:
             exc_html += self.generate_frame_html(frame, center_lineno, is_collapsed)
             is_collapsed = True
 
-        error = f"{traceback_obj.exc_type.__name__}: {traceback_obj}"
+        error = f"{traceback_obj.exc_type.__name__}: {html.escape(traceback_obj)}"
 
         return TEMPLATE.format(styles=STYLES, js=JS, error=error, exc_html=exc_html)