getchar.c in Vim before 8.1.1365 and Neovim before 0.3.6 allows remote attackers to execute arbitrary OS commands via the :source! command in a modeline, as demonstrated by execute in Vim, and assert_fails or nvim_input in Neovim.
https://www.debian.org/security/2019/dsa-4487
https://www.debian.org/security/2019/dsa-4467
https://usn.ubuntu.com/4016-2/
https://usn.ubuntu.com/4016-1/
https://support.f5.com/csp/article/K93144355?utm_source=f5support&%3Butm_medium=RSS
https://support.f5.com/csp/article/K93144355
https://security.gentoo.org/glsa/202003-04
https://seclists.org/bugtraq/2019/Jun/33
https://seclists.org/bugtraq/2019/Jul/39
https://lists.debian.org/debian-lts-announce/2019/08/msg00003.html
https://github.com/vim/vim/commit/53575521406739cf20bbe4e384d88e7dca11f040
https://github.com/numirias/security/blob/master/doc/2019-06-04_ace-vim-neovim.md
https://github.com/neovim/neovim/pull/10082
https://bugs.debian.org/930024
https://bugs.debian.org/930020
https://access.redhat.com/errata/RHSA-2019:1947
https://access.redhat.com/errata/RHSA-2019:1793
https://access.redhat.com/errata/RHSA-2019:1774
https://access.redhat.com/errata/RHSA-2019:1619
http://www.securityfocus.com/bid/108724
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00075.html
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00050.html
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00034.html
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00037.html
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00036.html
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00031.html