CVE-2021-22663
📋 TL;DR
CVE-2021-22663 is an out-of-bounds read vulnerability in Cscape software that allows arbitrary code execution when parsing malicious project files. Attackers can exploit this to run code with the same privileges as the Cscape process. All users running Cscape versions prior to 9.90 SP3.5 are affected.
💻 Affected Systems
- Cscape
📦 What is this software?
Cscape by Hornerautomation
Cscape by Siemens
Cscape by Siemens
Cscape by Siemens
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through remote code execution, potentially leading to industrial control system manipulation, data theft, or ransomware deployment.
Likely Case
Local privilege escalation or system compromise when users open malicious project files, potentially disrupting industrial operations.
If Mitigated
Limited impact with proper network segmentation and user privilege restrictions, potentially only causing application crashes.
🎯 Exploit Status
Exploitation requires user interaction to open malicious project files; no public exploit code is known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 9.90 SP3.5 or later
Vendor Advisory: https://us-cert.cisa.gov/ics/advisories/icsa-21-035-02
Restart Required: Yes
Instructions:
1. Download Cscape version 9.90 SP3.5 or later from official Eaton website. 2. Close all Cscape instances. 3. Run the installer with administrative privileges. 4. Follow installation prompts. 5. Restart system if prompted.
🔧 Temporary Workarounds
Restrict project file sources
allOnly open project files from trusted sources and implement file validation procedures.
User privilege reduction
windowsRun Cscape with limited user privileges to reduce impact of successful exploitation.
🧯 If You Can't Patch
- Implement network segmentation to isolate Cscape systems from critical networks
- Deploy application whitelisting to prevent execution of unauthorized code
🔍 How to Verify
Check if Vulnerable:
Check Cscape version via Help > About menu; versions below 9.90 SP3.5 are vulnerable.Check Version:
Not applicable - check via application GUI Help > AboutVerify Fix Applied:
Verify version is 9.90 SP3.5 or higher in Help > About menu.📡 Detection & Monitoring
Log Indicators:
- Application crashes when opening project files
- Unusual process creation from Cscape.exe
Network Indicators:
- Unexpected network connections from Cscape process
- File downloads to Cscape systems
SIEM Query:
Process Creation where Image contains 'Cscape.exe' and CommandLine contains unusual parameters