Security updates for Monday

Security updates have been issued by Debian (ark, netty, netty-3.9, qemu, squid3, and xorg-server), Fedora (chromium), Gentoo (dovecot and gnutls), Mageia (ansible, postgresql, and python-rsa), openSUSE (curl, freerdp, libX11, php7, squid, and xorg-x11-server), Oracle (kernel), Red Hat (thunderbird), Slackware (gnutls), and SUSE (firefox, kernel, and thunderbird).