JustAnotherOldGuy quotes Threatpost:
A high-severity bug impacting two popular command-line text editing applications, Vim and Neovim, allow remote attackers to execute arbitrary OS commands. Security researcher Armin Razmjou warned that exploiting the bug is as easy as tricking a target into clicking on a specially crafted text file in either editor. Razmjou outlined his research and created a proof-of-concept (PoC) attack demonstrating how an adversary can compromise a Linux system via Vim or Neowim. He said Vim versions before 8.1.1365 and Neovim before 0.3.6 are vulnerable to arbitrary code execution…
Vim and Neovim have both released patches for the bug (CVE-2019-12735) that the National Institute of Standards and Technology warns, “allows remote attackers to execute arbitrary OS commands via the :source! command in a modeline.”
“Beyond patching, it’s recommended to disable modelines in the vimrc (set nomodeline), to use the securemodelinesplugin, or to disable modelineexpr (since patch 8.1.1366, Vim-only) to disallow expressions in modelines,” the researcher said.