CVE-2021-22669
📋 TL;DR
This vulnerability allows low-privileged users in Advantech WebAccess/SCADA to reset administrator passwords and gain full system control through privilege escalation. It affects WebAccess/SCADA versions 9.0.1 and earlier. The flaw exists in the default permissions of the Project Management page.
💻 Affected Systems
- Advantech WebAccess/SCADA
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker gains full administrative control over the SCADA system, potentially manipulating industrial processes, stealing sensitive data, or causing physical damage to critical infrastructure.
Likely Case
Malicious insiders or compromised low-privileged accounts escalate to administrator privileges, enabling data theft, system manipulation, and persistence establishment.
If Mitigated
With proper network segmentation and access controls, impact is limited to the WebAccess/SCADA system itself rather than broader industrial networks.
🎯 Exploit Status
Requires low-privileged credentials but exploitation is straightforward through the web interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 9.0.2 or later
Vendor Advisory: https://us-cert.cisa.gov/ics/advisories/icsa-21-103-02
Restart Required: Yes
Instructions:
1. Download WebAccess/SCADA version 9.0.2 or later from Advantech. 2. Backup current configuration. 3. Install the update following vendor instructions. 4. Restart the WebAccess/SCADA service.
🔧 Temporary Workarounds
Restrict Access to WebAccess Portal
allLimit network access to the WebAccess/SCADA portal to only authorized administrators using firewall rules.
Implement Strong Authentication
allRequire multi-factor authentication for all WebAccess/SCADA users, especially low-privileged accounts.
🧯 If You Can't Patch
- Segment the WebAccess/SCADA network from other industrial control systems to limit lateral movement.
- Implement strict monitoring of user privilege changes and administrator account modifications.
🔍 How to Verify
Check if Vulnerable:
Check WebAccess/SCADA version in the application interface or installation directory. Versions 9.0.1 and earlier are vulnerable.Check Version:
Check the WebAccess/SCADA web interface login page or installation directory for version information.Verify Fix Applied:
Verify installation of version 9.0.2 or later and test that low-privileged users cannot access administrator password reset functionality.📡 Detection & Monitoring
Log Indicators:
- Unusual administrator password reset events
- Multiple failed login attempts followed by successful login from same low-privileged account
- User privilege escalation logs
Network Indicators:
- HTTP POST requests to password reset endpoints from non-admin accounts
- Unusual access patterns to Project Management page
SIEM Query:
source="webaccess_logs" AND (event="password_reset" OR event="privilege_change") AND user_role="low_privilege"