Update detection-rules/attachment_microsoft_image_lure_qr_code.yml

Co-authored-by: Ross Wolf <[email protected]>

detection-rules/attachment_microsoft_image_lure_qr_code.yml

@@ -38,7 +38,7 @@ source: |
                             )
                             
                             // or the body is null 
-                            or length(body.current_thread.text) is null
+                            or body.current_thread.text is null
                             or body.current_thread.text == ""
 
                             // or the subject contains authentication/urgency verbiage