diff --git a/backend/src/ee/routes/v1/dynamic-secret-router.ts b/backend/src/ee/routes/v1/dynamic-secret-router.ts
index ba2a5e4eb..bf5cce7d5 100644
--- a/backend/src/ee/routes/v1/dynamic-secret-router.ts
+++ b/backend/src/ee/routes/v1/dynamic-secret-router.ts
@@ -29,6 +29,7 @@ const validateUsernameTemplateCharacters = characterValidator([
 const userTemplateSchema = z
   .string()
   .trim()
+  .max(255)
   .refine((el) => validateUsernameTemplateCharacters(el))
   .refine((el) =>
     isValidHandleBarTemplate(el, {