CVE-2025-13827
📋 TL;DR
This vulnerability allows attackers to upload arbitrary files through the GrapesJS Builder component due to insufficient file type restrictions. If the media folder where files are stored is configured to execute code, this can lead to remote code execution. This affects Mautic users with the vulnerable GrapesJS Builder component enabled.
💻 Affected Systems
- Mautic
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data exfiltration, and lateral movement within the network.
Likely Case
File upload leading to web shell deployment and limited server access, potentially enabling further exploitation.
If Mitigated
File upload limited to non-executable types or media folder properly secured to prevent code execution.
🎯 Exploit Status
Exploitation requires authentication to access the GrapesJS Builder interface. File upload restrictions bypass is straightforward once authenticated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Mautic security advisory for specific patched version
Vendor Advisory: https://github.com/mautic/mautic/security/advisories/GHSA-5xw2-57jx-pgjp
Restart Required: No
Instructions:
1. Update Mautic to the latest patched version. 2. Apply the security patch from the vendor advisory. 3. Verify the fix by testing file upload restrictions.
🔧 Temporary Workarounds
Restrict media folder execution
allConfigure web server to prevent execution of uploaded files in media directories
For Apache: Add 'Options -ExecCGI -Includes' to media folder .htaccess
For Nginx: Add 'location ~* \.(php|pl|py|rb)$ { deny all; }' to media folder config
Disable GrapesJS Builder
allTemporarily disable the vulnerable component if not essential
Disable via Mautic admin interface or remove/rename GrapesJS Builder plugin files
🧯 If You Can't Patch
- Implement strict file upload validation at the application level
- Configure web application firewall to block suspicious file upload patterns
🔍 How to Verify
Check if Vulnerable:
Test if you can upload executable files (e.g., .php, .py) through the GrapesJS Builder interfaceCheck Version:
Check Mautic version in admin dashboard or via application filesVerify Fix Applied:
Attempt to upload restricted file types and verify they are rejected📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to media directories
- Multiple failed upload attempts followed by successful upload of executable file
Network Indicators:
- HTTP POST requests to file upload endpoints with executable file extensions
SIEM Query:
source="web_logs" AND (uri_path="/media/upload" OR uri_path="/builder/upload") AND file_extension IN ("php", "py", "pl", "rb")