CVE-2023-5344 – CVE-2023-5344 is a heap-based buffer overflow v... (How to Fix)

Q: What is the severity of CVE-2023-5344?

CVE-2023-5344 has a CVSS score of 7.5 (HIGH). CVE-2023-5344 is a heap-based buffer overflow vulnerability in Vim text editor versions prior to 9.0.1969. Attackers can exploit this by tricking users into opening specially crafted files, potentially leading to arbitrary code execution. This affects all users running vulnerable Vim versions on any platform.

📋 TL;DR

CVE-2023-5344 is a heap-based buffer overflow vulnerability in Vim text editor versions prior to 9.0.1969. Attackers can exploit this by tricking users into opening specially crafted files, potentially leading to arbitrary code execution. This affects all users running vulnerable Vim versions on any platform.

💻 Affected Systems

Products:

Vim

Versions: All versions prior to 9.0.1969

Operating Systems: All platforms running Vim (Linux, Windows, macOS, BSD, etc.)

Default Config Vulnerable: ⚠️ Yes

Notes: All standard installations are vulnerable. The vulnerability is triggered when processing certain file types in Vim.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote code execution with the privileges of the Vim user, potentially leading to full system compromise, data theft, or lateral movement.

🟠

Likely Case

Application crash (denial of service) or limited code execution depending on exploit sophistication and system protections.

🟢

If Mitigated

Application crash with no code execution if exploit fails or protections like ASLR/PIE are effective.

🌐 Internet-Facing: LOW (Vim is typically not directly internet-facing, though could be exposed via SSH or web interfaces in rare cases).

🏢 Internal Only: MEDIUM (Attackers with internal access could exploit via malicious files, but requires user interaction to open them in Vim).

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: LIKELY

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Exploitation requires user interaction (opening a malicious file). Proof-of-concept details are available in public disclosures.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: 9.0.1969 and later

Vendor Advisory: https://github.com/vim/vim/commit/3bd7fa12e146c6051490d048a4acbfba974eeb04

Restart Required: No

Instructions:

1. Update Vim to version 9.0.1969 or later using your system's package manager. 2. For Linux: Use 'sudo apt update && sudo apt upgrade vim' (Debian/Ubuntu) or 'sudo yum update vim' (RHEL/CentOS). 3. For Windows: Download latest installer from vim.org. 4. For macOS: Use Homebrew 'brew upgrade vim'. 5. For source: Clone latest from GitHub and compile.

🔧 Temporary Workarounds

Disable vulnerable file processing

all

Avoid opening untrusted files in Vim, especially those with unusual extensions or from unknown sources.

Use alternative text editors

all

Temporarily use nano, emacs, or other editors for untrusted files until patched.

🧯 If You Can't Patch

Restrict Vim usage to trusted users only via access controls.
Implement application allowlisting to prevent unauthorized Vim execution.

🔍 How to Verify

Check if Vulnerable:

Run 'vim --version' and check if version is below 9.0.1969.

Check Version:

vim --version | head -1

Verify Fix Applied:

Run 'vim --version' and confirm version is 9.0.1969 or higher.

📡 Detection & Monitoring

Log Indicators:

Vim crash logs, segmentation fault errors in system logs

Network Indicators:

Unusual file transfers to systems running Vim

SIEM Query:

Process execution logs showing vim opening suspicious files or crash events

📊 Metadata

CVE ID: CVE-2023-5344

CVSS v3 Score: 7.5 (HIGH)

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE: CWE-122

Published: October 2, 2023

Last Updated: November 3, 2025

🔗 References

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🔗 Related Vulnerabilities

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