diff --git a/Lib/BaseHTTPServer.py b/Lib/BaseHTTPServer.py
index c97c762..da04315 100644
--- a/Lib/BaseHTTPServer.py
+++ b/Lib/BaseHTTPServer.py
@@ -310,7 +310,13 @@
 
         """
         try:
-            self.raw_requestline = self.rfile.readline()
+            self.raw_requestline = self.rfile.readline(65537)
+            if len(self.raw_requestline) > 65536:
+                self.requestline = ''
+                self.request_version = ''
+                self.command = ''
+                self.send_error(414)
+                return
             if not self.raw_requestline:
                 self.close_connection = 1
                 return