diff --git a/frappe/utils/file_manager.py b/frappe/utils/file_manager.py
index ffe337df0b..839c3e1b20 100644
--- a/frappe/utils/file_manager.py
+++ b/frappe/utils/file_manager.py
@@ -429,7 +429,7 @@ def get_random_filename(extn=None, content_type=None):
 
 	return random_string(7) + (extn or "")
 
-@frappe.whitelist()
+@frappe.whitelist(allow_guest=True)
 def validate_filename(filename):
 	from frappe.utils import now_datetime
 	timestamp = now_datetime().strftime(" %Y-%m-%d %H:%M:%S")
@@ -450,4 +450,4 @@ def add_attachments(doctype, name, attachments):
 			f = save_url(attach.file_url, attach.file_name, doctype, name, "Home/Attachments", attach.is_private)
 			files.append(f)
 
-	return files
\ No newline at end of file
+	return files