This indicates an attack attempt to exploit a command execution vulnerability in Vim.
The vulnerability is due to an error when the vulnerable software attempts to handle a maliciously crafted modeline. An attacker can exploit this by tricking an unsuspecting user into loading a malicious modeline and execute arbitrary code within the context of the application.
Vim prior to 8.0.0056
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.