Lite XL versions 2.1.8 and prior automatically execute the .lite_project.lua file when opening a project directory, without prompting the user for confirmation. The .lite_project.lua file is intended for project-specific configuration but can contain executable Lua logic. This behavior could allow execution of untrusted Lua code if a user opens a malicious project, potentially leading to arbitrary code execution with the privileges of the Lite XL process.

Lite XL versions 2.1.8 and prior contain a vulnerability in the system.exec function, which allowed arbitrary command execution through unsanitized shell command construction. This function was used in project directory launching (core.lua), drag-and-drop file handling (rootview.lua), and the “open in system” command in the treeview plugin (treeview.lua). If an attacker could influence input to system.exec, they might execute arbitrary commands with the privileges of the Lite XL process.