Buffer Over-read in vim/vim

Vulnerability

A buffer over-read vulnerability exists in Vim (the vim command-line editor) prior to version 8.2.4974. The flaw resides in the core editor code and is triggered when opening a specially crafted file. No specific configuration beyond standard usage is required for the vulnerable code path to be reached.

Exploitation

An attacker must deliver a malicious file to the victim and convince them to open it with Vim. No authentication or special network position is required; local access suffices. Once the file is opened, the buffer over-read occurs during parsing, potentially exposing adjacent memory contents.

Impact

Successful exploitation may lead to a crash of the Vim process or unintended disclosure of memory contents, which could include sensitive data. The vulnerability is limited to a buffer over-read (not write), so arbitrary code execution is not directly implied.

Mitigation

The vulnerability is fixed in Vim version 8.2.4974 (and later). Users should update to this version or newer. Distributions shipping older Vim packages (e.g., Fedora, macOS) have received updates via their respective security channels [1]. If an immediate patch is not available, users should avoid opening untrusted files in Vim until the update is applied.