CVE-2018-15888
📋 TL;DR
ASPCMS 2.5.6 allows unauthenticated users to register accounts with super administrator privileges during registration. This vulnerability enables attackers to gain full administrative control over affected ASPCMS installations. All systems running the vulnerable version are affected.
💻 Affected Systems
- ASPCMS
📦 What is this software?
Aspcms by Aspcms
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the CMS installation allowing attackers to modify content, steal data, install backdoors, and potentially compromise the underlying server.
Likely Case
Attackers create administrator accounts to deface websites, inject malicious content, or steal sensitive information stored in the CMS.
If Mitigated
If proper access controls and input validation are implemented, the vulnerability would be prevented at the registration endpoint.
🎯 Exploit Status
Exploitation requires sending a specially crafted HTTP POST request to the registration endpoint with the administrator GroupID parameter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.5.7 or later
Vendor Advisory: Not available - ASPCMS appears to be discontinued
Restart Required: No
Instructions:
1. Upgrade to ASPCMS 2.5.7 or later if available. 2. If upgrade not possible, manually patch the /member/reg.asp file to validate GroupID parameter. 3. Remove or disable user registration if not required.
🔧 Temporary Workarounds
Disable User Registration
windowsRemove or disable the user registration functionality entirely
Rename or remove /member/reg.asp file
Disable registration in ASPCMS admin panel if option exists
Implement Input Validation
windowsAdd server-side validation to reject GroupID parameter in registration requests
Edit /member/reg.asp to validate GroupID parameter before processing
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block requests containing administrator GroupID parameters
- Monitor registration logs for suspicious activity and implement rate limiting on registration endpoint
🔍 How to Verify
Check if Vulnerable:
Attempt to register a user with GroupID=1 parameter via POST to /member/reg.asp and check if account gets administrator privilegesCheck Version:
Check ASPCMS version in admin panel or footer of websiteVerify Fix Applied:
Verify that registration requests with GroupID parameter are rejected or properly validated📡 Detection & Monitoring
Log Indicators:
- Unusual registration requests with GroupID parameter
- Multiple registration attempts from same IP
- New administrator accounts created via registration
Network Indicators:
- HTTP POST requests to /member/reg.asp with GroupID parameter
- Traffic patterns showing registration abuse
SIEM Query:
source="web_server" AND (uri="/member/reg.asp" AND method="POST" AND (param="GroupID" OR body CONTAINS "GroupID"))