Apache SpamAssassin 3.4.2 fixes a local user code injection in the meta rule syntax.
https://usn.ubuntu.com/3811-3/
https://usn.ubuntu.com/3811-1/
https://security.gentoo.org/glsa/201812-07
https://lists.debian.org/debian-lts-announce/2018/11/msg00016.html
https://access.redhat.com/errata/RHSA-2018:2916
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00002.html