diff --git a/objects/email/definition.json b/objects/email/definition.json
index aaa768d..53853b5 100644
--- a/objects/email/definition.json
+++ b/objects/email/definition.json
@@ -51,7 +51,7 @@
       "multiple": true
     },
     "x-mailer": {
-      "misp-attribute": "email-xmailer",
+      "misp-attribute": "email-x-mailer",
       "misp-usage-frequency": 0,
       "categories": [
         "Payload delivery"