Vim Modeline Vulnerability: How a Crafted File Can Hijack Your System

The Vim project disclosed CVE-2026-34982, a high-severity modeline sandbox bypass (CVSS 8.2) affecting all Vim versions prior to 9.2.0276. Missing security flags on options such as complete, guitabtooltip, and printheader allow modelines to execute code; combined with a lack of check_secure() in mapset(), an attacker can achieve arbitrary command execution with the privileges of the user opening a crafted file. Users are advised to update to Vim 9.2.0276 or later.