The keyfile settings backend in GNOME GLib (aka glib2.0) before 2.60.0 creates directories using g_file_make_directory_with_parents (kfsb->dir, NULL, NULL) and files using g_file_replace_contents (kfsb->file, contents, length, NULL, FALSE, G_FILE_CREATE_REPLACE_DESTINATION, NULL, NULL, NULL). Consequently, it does not properly restrict directory (and file) permissions. Instead, for directories, 0777 permissions are used; for files, default file permissions are used. This is similar to CVE-2019-12450.

file_copy_fallback in gio/gfile.c in GNOME GLib 2.15.0 through 2.61.1 does not properly restrict file permissions while a copy operation is in progress. Instead, default permissions are used.