diff --git a/modules/distribution/src/repository/resources/conf/default.json b/modules/distribution/src/repository/resources/conf/default.json
index 518f13fb35..ea9be0b815 100644
--- a/modules/distribution/src/repository/resources/conf/default.json
+++ b/modules/distribution/src/repository/resources/conf/default.json
@@ -48,7 +48,7 @@
   "authorization_manager.properties.GroupAndRoleSeparationEnabled": "true",
   "authorization_manager.properties.GroupAndRoleSeparationImprovementsEnabled": "true",
 
-  "user_store.properties.UsernameJavaScriptRegEx": "^[\\S]{3,50}$",
+  "user_store.properties.UsernameJavaScriptRegEx": "^[^\\s*?%]{3,50}$",
 
   "default_management_ui.path": "console",
   "legacy_authz_runtime.enable": false
diff --git a/modules/distribution/src/repository/resources/conf/infer.json b/modules/distribution/src/repository/resources/conf/infer.json
index 688032ccba..fa49b39190 100644
--- a/modules/distribution/src/repository/resources/conf/infer.json
+++ b/modules/distribution/src/repository/resources/conf/infer.json
@@ -1,10 +1,10 @@
 {
   "user_store.type": {
     "database": {
-      "user_store.properties.UsernameJavaRegEx": "^[\\S]{3,50}$"
+      "user_store.properties.UsernameJavaRegEx": "^[^\\s*?%]{3,50}$"
     },
     "database_unique_id": {
-      "user_store.properties.UsernameJavaRegEx": "^[\\S]{3,50}$"
+      "user_store.properties.UsernameJavaRegEx": "^[^\\s*?%]{3,50}$"
     },
     "read_only_ldap": {
       "user_store.properties.UsernameJavaRegEx": "[a-zA-Z0-9._\\-|//]{3,50}$"