CVE-2019-10938
📋 TL;DR
This vulnerability allows unauthenticated attackers with network access to execute arbitrary code on affected Siemens industrial devices before firmware verification occurs. It affects SIPROTEC 5 protection devices and Siemens Power Meters used in electrical infrastructure. The CVSS 9.8 score indicates critical severity with high potential impact.
💻 Affected Systems
- SIPROTEC 5 devices with CPU variants CP200
- SIPROTEC 5 devices with CPU variants CP300
- SIPROTEC 5 devices with CPU variants CP100
- Siemens Power Meters Series 9410
- Siemens Power Meters Series 9810
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of industrial control systems, allowing attackers to manipulate power grid operations, cause equipment damage, or disrupt critical infrastructure.
Likely Case
Unauthorized access to device configuration, firmware manipulation, or disruption of monitoring and protection functions in electrical systems.
If Mitigated
Limited impact if devices are properly segmented and access-controlled, though the vulnerability remains exploitable within the network segment.
🎯 Exploit Status
No public exploitation known at advisory publication, but unauthenticated network access makes exploitation straightforward for skilled attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: CP200: V7.59 or higher; CP300/CP100: V8.01 or higher; Series 9410: V2.2.1 or higher; Series 9810: Contact Siemens for updates
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-352504.pdf
Restart Required: Yes
Instructions:
1. Download firmware updates from Siemens Industry Online Support. 2. Follow device-specific update procedures in manuals. 3. Apply updates during maintenance windows. 4. Verify successful update and functionality.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected devices in dedicated network segments with strict access controls.
Access Control Lists
allImplement firewall rules to restrict network access to authorized management stations only.
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to limit access to only necessary IP addresses
- Monitor network traffic to/from affected devices for suspicious activity and implement intrusion detection
🔍 How to Verify
Check if Vulnerable:
Check device firmware version via device web interface or management software against affected version ranges.Check Version:
Device-specific commands vary; typically accessed via web interface at device IP or using DIGSI 5 software.Verify Fix Applied:
Confirm firmware version is at or above patched versions: CP200 ≥ V7.59, CP300/CP100 ≥ V8.01, Series 9410 ≥ V2.2.1📡 Detection & Monitoring
Log Indicators:
- Unauthorized firmware update attempts
- Unexpected device reboots
- Configuration changes from unknown sources
Network Indicators:
- Unusual network traffic to device management ports
- Firmware upload attempts from unauthorized IPs
SIEM Query:
source_ip NOT IN (authorized_management_ips) AND dest_port IN (device_management_ports) AND protocol IN (http, https, ftp, tftp)