KDE Kleopatra before 26.08.0 on Windows allows local users to obtain the privileges of a Kleopatra user, because there is an error in the mechanism (KUniqueService) for ensuring that only one instance is running.
https://kde.org/info/security/advisory-20260408-1.txt
https://github.com/KDE/kleopatra/releases
https://commits.kde.org/kleopatra/73471abb92d99c56354adb582bfaec2764c22b79