CVE-2026-73073

A flaw was found in Vim, an open-source command-line text editor. An attacker could craft a malicious tags file that, when processed by Vim's C omni-completion feature, leads to insufficient escaping of input. This vulnerability allows for the execution of arbitrary Ex commands and, subsequently, operating-system commands on the user's system. Successful exploitation requires a user to open a C file from an attacker-controlled tree and invoke C omni-completion on a member access whose type is resolved from the malicious tags file.

This is an Important vulnerability in Vim where a local attacker could achieve arbitrary command execution. By crafting a malicious tags file and enticing a user to open a C file from an untrusted source and invoke C omni-completion, the attacker could execute arbitrary commands in the context of the user running Vim. This is considered Important due to the potential for full user-level compromise, despite requiring specific user interaction and a crafted file.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this issue, users should avoid opening C source files from untrusted sources, especially when accompanied by untrusted tags files. Exercise caution when invoking C omni-completion (CTRL-X CTRL-O) on files from unknown or suspicious origins.