CVE-2024-37040
📋 TL;DR
This CVE describes a classic buffer overflow vulnerability in Schneider Electric devices that allows authenticated users to crash the device by sending malformed HTTP requests. It affects users with access to the web interface of vulnerable Schneider Electric products. The vulnerability could cause denial of service but does not appear to allow remote code execution.
💻 Affected Systems
- Schneider Electric EcoStruxure Control Expert
- Schneider Electric EcoStruxure Process Expert
- Schneider Electric Modicon M580
- Schneider Electric Modicon M340
📦 What is this software?
Sage Rtu Firmware by Schneider Electric
⚠️ Risk & Real-World Impact
Worst Case
Device crash leading to denial of service, potentially disrupting industrial operations or critical infrastructure.
Likely Case
Temporary service interruption requiring device reboot, causing operational downtime.
If Mitigated
Minimal impact with proper network segmentation and access controls limiting web interface exposure.
🎯 Exploit Status
Exploitation requires valid credentials for web interface access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to SEVD-2024-163-05 for specific patched versions
Vendor Advisory: https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2024-163-05&p_enDocType=Security+and+Safety+Notice&p_File_Name=SEVD-2024-163-05.pdf
Restart Required: Yes
Instructions:
1. Download firmware update from Schneider Electric portal. 2. Backup current configuration. 3. Apply firmware update following vendor instructions. 4. Reboot device. 5. Verify update and restore configuration if needed.
🔧 Temporary Workarounds
Restrict Web Interface Access
linuxLimit network access to device web interface using firewall rules.
iptables -A INPUT -p tcp --dport 80 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Disable Web Interface
allTurn off web services if not required for operations.
Check device configuration manual for web service disable procedure
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable devices from untrusted networks.
- Enforce strong authentication and limit user access to only necessary personnel.
🔍 How to Verify
Check if Vulnerable:
Check device firmware version against vulnerable versions listed in SEVD-2024-163-05.Check Version:
Check device web interface or use vendor-specific CLI commands (varies by product).Verify Fix Applied:
Verify firmware version matches patched versions from vendor advisory and test web interface functionality.📡 Detection & Monitoring
Log Indicators:
- Multiple malformed HTTP requests to device web interface
- Device crash/reboot logs
- Web service failure events
Network Indicators:
- Unusual HTTP traffic patterns to industrial device web interfaces
- Requests with oversized headers or parameters
SIEM Query:
source="industrial_device" AND (http_request_size>threshold OR http_status=500)