CVE-2025-6873
📋 TL;DR
This vulnerability allows remote attackers to upload arbitrary files to Simple Company Website 1.0 via the /classes/Users.php?f=save endpoint. Attackers can potentially upload malicious files like web shells to gain unauthorized access or execute code. Organizations using SourceCodester Simple Company Website 1.0 are affected.
💻 Affected Systems
- SourceCodester Simple Company Website
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise via web shell leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Unauthorized file upload leading to web shell installation and limited server access.
If Mitigated
File upload blocked or sanitized, preventing malicious file execution.
🎯 Exploit Status
Public proof-of-concept available on GitHub, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.sourcecodester.com/
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a newer version if available or implementing workarounds.
🔧 Temporary Workarounds
Restrict file upload types
allImplement server-side validation to only allow specific file extensions (e.g., .jpg, .png) and verify file content.
Disable file upload functionality
allTemporarily disable the /classes/Users.php?f=save endpoint or file upload feature if not essential.
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block requests to /classes/Users.php?f=save with suspicious file uploads.
- Restrict network access to the application to trusted IP addresses only.
🔍 How to Verify
Check if Vulnerable:
Attempt to upload a file with a malicious extension (e.g., .php) via the /classes/Users.php?f=save endpoint and check if it's accepted.Check Version:
Check the application's version in its configuration files or admin panel.Verify Fix Applied:
Verify that file upload validation rejects unauthorized file types and that uploaded files are stored in a non-executable directory.📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /classes/Users.php?f=save with unusual file names or extensions
- Files with suspicious extensions (e.g., .php, .jsp) appearing in upload directories
Network Indicators:
- Unusual outbound connections from the web server post-file upload
- Traffic patterns indicating file upload attempts to the vulnerable endpoint
SIEM Query:
source="web_server_logs" AND uri="/classes/Users.php?f=save" AND method="POST" AND (file_extension="php" OR file_extension="jsp" OR file_extension="asp")