CVE-2025-25765
📋 TL;DR
MRCMS v3.1.2 contains an arbitrary file write vulnerability in the /file/save.do component that allows attackers to write arbitrary files to the server. This affects all systems running MRCMS v3.1.2. The vulnerability could lead to web shell deployment, configuration modification, or denial of service.
💻 Affected Systems
- MRCMS
📦 What is this software?
Mrcms by Mrcms
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise via web shell deployment leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Web shell deployment allowing persistent access, data exfiltration, or defacement of the website.
If Mitigated
Limited impact if file system permissions restrict write access to non-critical directories and web root.
🎯 Exploit Status
The vulnerability requires authentication to the /file/save.do endpoint. Exploitation involves sending crafted requests to write arbitrary files.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: No official vendor advisory found
Restart Required: No
Instructions:
1. Monitor MRCMS vendor channels for security updates. 2. Check if newer versions beyond v3.1.2 address this vulnerability. 3. Apply any available patches immediately when released.
🔧 Temporary Workarounds
Restrict access to /file/save.do endpoint
allBlock or restrict access to the vulnerable endpoint using web server configuration or WAF rules.
# Apache: RewriteRule ^/file/save\.do$ - [F]
# Nginx: location ~ ^/file/save\.do$ { deny all; }
Implement strict file upload validation
allAdd server-side validation to restrict file types, names, and paths that can be written.
🧯 If You Can't Patch
- Implement network segmentation to isolate MRCMS instances from critical systems
- Deploy web application firewall (WAF) with rules to detect and block arbitrary file write attempts
🔍 How to Verify
Check if Vulnerable:
Check if MRCMS version is 3.1.2 and if /file/save.do endpoint is accessible with write permissions.Check Version:
Check MRCMS configuration files or admin panel for version informationVerify Fix Applied:
Test if arbitrary file writes are still possible after applying mitigations by attempting controlled file write tests.📡 Detection & Monitoring
Log Indicators:
- Unusual file write operations in web server logs
- Multiple POST requests to /file/save.do with suspicious file names or paths
- Web shell file creation in unexpected directories
Network Indicators:
- HTTP POST requests to /file/save.do with file write parameters
- Traffic patterns indicating file upload attempts to non-standard locations
SIEM Query:
web.url:*file/save.do AND (http.method:POST OR web.status:200) AND (file.extension:php OR file.extension:jsp OR file.extension:asp)