diff --git a/functions/_headers b/functions/_headers
index e822888..d3f3957 100644
--- a/functions/_headers
+++ b/functions/_headers
@@ -1,3 +1,4 @@
 /.well-known/matrix/*
+  X-Content-Type-Options: nosniff
   Content-Type: application/json
   Access-Control-Allow-Origin: *
\ No newline at end of file