CVE-2024-41798
📋 TL;DR
This vulnerability allows attackers to bypass the weak 4-digit PIN protection on SENTRON 7KM PAC3200 devices via Modbus TCP interface. Attackers can brute-force the PIN or intercept it through cleartext communication, gaining administrative access. All versions of SENTRON 7KM PAC3200 devices are affected.
💻 Affected Systems
- SENTRON 7KM PAC3200
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Full administrative control of industrial power monitoring devices, allowing manipulation of power measurements, configuration changes, or disruption of monitoring systems.
Likely Case
Unauthorized access to device configuration and monitoring data, potentially enabling industrial espionage or manipulation of power readings.
If Mitigated
Limited impact if devices are isolated from untrusted networks and Modbus TCP access is restricted.
🎯 Exploit Status
Exploitation requires network access to Modbus TCP port (default 502) but no authentication. Brute-forcing 4-digit PIN is trivial.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: N/A
Vendor Advisory: https://cert-portal.siemens.com/productcert/html/ssa-850560.html
Restart Required: No
Instructions:
No official patch available. Follow vendor advisory for mitigation guidance.
🔧 Temporary Workarounds
Network Segmentation
allIsolate SENTRON devices from untrusted networks and restrict Modbus TCP access to authorized systems only.
Firewall Rules
allImplement strict firewall rules to block unauthorized access to Modbus TCP port 502.
🧯 If You Can't Patch
- Implement network segmentation to isolate vulnerable devices
- Monitor Modbus TCP traffic for brute-force attempts and unauthorized access
🔍 How to Verify
Check if Vulnerable:
Check if device is SENTRON 7KM PAC3200 with Modbus TCP enabled and using 4-digit PIN authentication.Check Version:
Check device model and firmware version via device interface or management console.Verify Fix Applied:
Verify network segmentation is in place and Modbus TCP port 502 is not accessible from untrusted networks.📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts on Modbus TCP
- Unusual administrative access patterns
Network Indicators:
- Brute-force attempts on port 502
- Cleartext Modbus traffic containing authentication data
SIEM Query:
source_port:502 AND (event_type:authentication_failure OR protocol:modbus)