CVE-2025-27423
📋 TL;DR
This vulnerability in Vim's tar.vim plugin allows arbitrary shell command execution when opening specially crafted tar archives. Attackers can exploit this by tricking users into opening malicious tar files, potentially leading to remote code execution. Users running Vim versions 9.1.0858 through 9.1.1163 with the tar.vim plugin enabled are affected.
💻 Affected Systems
- Vim with tar.vim plugin
📦 What is this software?
Vim by Vim
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise via remote code execution, allowing attackers to install malware, exfiltrate data, or pivot to other systems.
Likely Case
Local privilege escalation or arbitrary file read/write when users open malicious tar files, potentially leading to credential theft or lateral movement.
If Mitigated
Limited impact if users only open trusted tar files and have restricted shell permissions, though risk remains for privilege escalation.
🎯 Exploit Status
Exploitation requires user interaction to open malicious tar file. Proof-of-concept exists in advisory references.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Vim 9.1.1164 or later
Vendor Advisory: https://github.com/vim/vim/security/advisories/GHSA-wfmf-8626-q3r3
Restart Required: No
Instructions:
1. Update Vim to version 9.1.1164 or later using your package manager. 2. For source installations: git pull from official repository and rebuild. 3. Verify patch application with version check.
🔧 Temporary Workarounds
Disable tar.vim plugin
allPrevents tar file handling through vulnerable plugin
echo 'let g:loaded_tarPlugin = 1' >> ~/.vimrc
Restrict shell permissions
linuxLimit shell capabilities to reduce impact
chmod 700 /bin/bash
set shell=/bin/false in .vimrc
🧯 If You Can't Patch
- Avoid opening tar files from untrusted sources in Vim
- Use alternative tar utilities (tar command line) instead of tar.vim plugin
🔍 How to Verify
Check if Vulnerable:
Check Vim version with 'vim --version' and verify if between 9.1.0858 and 9.1.1163Check Version:
vim --version | grep 'Included patches'Verify Fix Applied:
Confirm version is 9.1.1164 or later with 'vim --version | head -1'📡 Detection & Monitoring
Log Indicators:
- Unusual shell commands executed from Vim process
- Tar file openings followed by unexpected process spawns
Network Indicators:
- Outbound connections from Vim process to unexpected destinations
SIEM Query:
process_name:vim AND (process_cmdline:*tar* OR parent_process:tar)