Security updates for Monday

Security updates have been issued by Arch Linux (apache, go, haproxy, matrix-synapse, nasm, and powerdns-recursor), Debian (coturn, ghostscript, krb5, policykit-1, and qtbase-opensource-src), Fedora (wireshark), openSUSE (nodejs4, nodejs8, openssh, PackageKit, and wireshark), Oracle (qemu and thunderbird), Scientific Linux (thunderbird), and SUSE (avahi, krb5, and python-paramiko).