Privilege Escalation via D‑Bus ShowFolders Call in PCManFM-Qt

An issue was discovered in all versions of PCManFM-Qt starting from 1.1.0. When a regular file's path is passed as a URI in an org.freedesktop.FileManager1.ShowFolders D-Bus method call, PCManFM-Qt delegates to a different program (based on the file type) without user confirmation. This could be used to achieve code execution or circumvent network namespace restrictions. NOTE: those outcomes are potentially unwanted by most users; however, the behavior of the product does comply with the applicable specification, and a simplistic solution (ensuring that the URI does not name a regular file) may have adverse consequences for I/O.