CVE-2022-1720

What it actually does

Buffer over-read in grab_file_name allows out-of-bounds memory access leading to crash, memory corruption, or potential code execution when processing crafted input.

Why it matters to the business

Users running vulnerable Vim versions risk editor crashes, data corruption, or remote code execution when opening attacker-supplied files, potentially disrupting development workflows and requiring urgent patching across developer systems.

How an attack unfolds

An attacker crafts a file with malformed content that triggers the over-read when Vim calls grab_file_name during file handling; the victim opens the file in an affected Vim version, resulting in memory corruption that may be leveraged for code execution.

How to fix it

Upgrade vim/vim to commit 395bd1f6d3edc9f7edb5d1f2d7deaf5a9e3ab93c or later equivalent release; rebuild and redeploy all affected installations.

How to confirm the fix worked

Confirm Vim version reports 8.2.4956 or newer; test with known trigger files to verify absence of crash or corruption; review build logs for the fixed commit.

Typical attack path

1. Attacker creates malicious file designed to trigger buffer over-read in grab_file_name
2. Victim opens the file using vulnerable Vim (prior to 8.2.4956)
3. Vim processes the file name extraction, causing out-of-bounds read and memory corruption
4. Attacker leverages corruption for crash, data leak, or remote code execution

How to detect it

Review application logs and crash reports for Vim segmentation faults or memory errors during file open operations; monitor for unexpected process behavior when handling files from untrusted sources.

What your security team should do

• Immediately update all Vim installations to the fixed commit or patched release
• Scan developer environments and CI systems for vulnerable Vim binaries
• Block or sanitize untrusted files before opening in Vim until patches are applied