Paisa before 0.7.8 Path Traversal via Editor and Sheet API

Paisa before 0.7.8 contains a path traversal vulnerability in the GetFile, GetSheet, DeleteBackups, and DeleteSheetBackups handlers that lets unauthenticated attackers read files and delete backups through ../ sequences in file names. Attackers can send crafted names to the editor file and delete_backups endpoints to read any server-readable file and remove backup files outside the journal or sheets directory.