An issue was discovered in Smartstore (aka SmartStoreNET) before 4.1.0. Administration/Controllers/ImportController.cs allows path traversal (for copy and delete actions) in the ImportController.Create method via a TempFileName field.
https://github.com/smartstore/SmartStoreNET/issues/2112
https://github.com/smartstore/SmartStoreNET/commit/5ab1e37dc8d6415d04354e1a116f3d82e9555f5c