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.
https://usn.ubuntu.com/4049-2/
https://usn.ubuntu.com/4049-1/
https://security.netapp.com/advisory/ntap-20190806-0003/
https://lists.debian.org/debian-lts-announce/2019/08/msg00004.html
https://lists.debian.org/debian-lts-announce/2019/07/msg00029.html
https://gitlab.gnome.org/GNOME/glib/merge_requests/450
https://gitlab.gnome.org/GNOME/glib/issues/1658
https://gitlab.gnome.org/GNOME/glib/commit/5e4da714f00f6bfb2ccd6d73d61329c6f3a08429
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=931234#12
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00022.html