GNU Patch version 2.7.6 contains an input validation vulnerability when processing patch files, specifically the EDITOR_PROGRAM invocation (using ed) can result in code execution. This attack appear to be exploitable via a patch file processed via the patch utility. This is similar to FreeBSD's CVE-2015-1418 however although they share a common ancestry the code bases have diverged over time.
https://usn.ubuntu.com/3624-2/
https://usn.ubuntu.com/3624-1/
https://twitter.com/kurtseifried/status/982028968877436928
https://security.gentoo.org/glsa/201904-17
https://seclists.org/bugtraq/2019/Jul/54
https://seclists.org/bugtraq/2019/Aug/29
https://savannah.gnu.org/bugs/index.php?53566
https://lists.debian.org/debian-lts-announce/2018/04/msg00013.html
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=894667#19
https://access.redhat.com/errata/RHSA-2018:2097
https://access.redhat.com/errata/RHSA-2018:2096
https://access.redhat.com/errata/RHSA-2018:2095
https://access.redhat.com/errata/RHSA-2018:2094
https://access.redhat.com/errata/RHSA-2018:2093
https://access.redhat.com/errata/RHSA-2018:2092
https://access.redhat.com/errata/RHSA-2018:2091
https://access.redhat.com/errata/RHSA-2018:1200
https://access.redhat.com/errata/RHSA-2018:1199
http://rachelbythebay.com/w/2018/04/05/bangpatch/
http://packetstormsecurity.com/files/154124/GNU-patch-Command-Injection-Directory-Traversal.html