CVE-2024-23180
📋 TL;DR
This vulnerability allows authenticated attackers to upload specially crafted SVG files that bypass input validation in a-blog CMS, leading to remote code execution. It affects multiple versions of a-blog CMS across several series. Attackers must have authenticated access to exploit this vulnerability.
💻 Affected Systems
- a-blog CMS
📦 What is this software?
A Blog Cms by Appleple
A Blog Cms by Appleple
A Blog Cms by Appleple
A Blog Cms by Appleple
A Blog Cms by Appleple
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control over the web server, potentially leading to data theft, lateral movement, and persistent backdoor installation.
Likely Case
Attacker uploads malicious SVG file to execute arbitrary code, potentially compromising the web application and underlying server, leading to data exfiltration or ransomware deployment.
If Mitigated
With proper input validation and file upload restrictions, the attack would be blocked at the upload stage, preventing code execution.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward once authenticated. SVG file upload functionality is commonly available to authenticated users.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Ver.3.1.7, Ver.3.0.29, Ver.2.11.58, Ver.2.10.50
Vendor Advisory: https://developer.a-blogcms.jp/blog/news/JVN-34565930.html
Restart Required: No
Instructions:
1. Backup your current installation and database. 2. Download the patched version from the official a-blog CMS website. 3. Replace the affected files with the patched version. 4. Verify the installation works correctly.
🔧 Temporary Workarounds
Disable SVG file uploads
allTemporarily block SVG file uploads through web server configuration or application settings
# Apache: Add to .htaccess
<FilesMatch "\.svg$">
Order allow,deny
Deny from all
</FilesMatch>
# Nginx: Add to server block
location ~*\.svg$ {
deny all;
}
Restrict file upload permissions
allLimit which authenticated users can upload files to the system
# Review and modify user role permissions in a-blog CMS admin panel to restrict file upload capabilities
🧯 If You Can't Patch
- Implement strict input validation for all file uploads, specifically checking SVG file content for malicious code
- Deploy a Web Application Firewall (WAF) with rules to detect and block malicious SVG file uploads
🔍 How to Verify
Check if Vulnerable:
Check your a-blog CMS version in the admin panel or by examining the installation files. Compare against affected version ranges.Check Version:
# Check version in a-blog CMS admin dashboard or examine system configuration filesVerify Fix Applied:
After patching, verify the version number matches patched versions and test SVG file upload functionality with safe test files.📡 Detection & Monitoring
Log Indicators:
- Unusual SVG file uploads from authenticated users
- Multiple failed SVG upload attempts
- File uploads with suspicious filenames or content
Network Indicators:
- POST requests to file upload endpoints with SVG content
- Unusual outbound connections after SVG file uploads
SIEM Query:
source="web_server" AND (uri_path="*upload*" OR uri_path="*file*" OR method="POST") AND (file_extension="svg" OR content_type="image/svg+xml")