CVE-2025-59668
📋 TL;DR
A NULL pointer dereference vulnerability in Central Monitor CNS-6201 allows remote attackers to crash the device by sending a specially crafted UDP packet. This affects healthcare facilities using vulnerable versions of this patient monitoring system, potentially disrupting critical medical monitoring.
💻 Affected Systems
- Nihon Kohden Central Monitor CNS-6201
⚠️ 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
Complete device crash leading to loss of patient monitoring capabilities during critical care situations, potentially endangering patient safety.
Likely Case
Device becomes unresponsive requiring manual reboot, causing temporary monitoring gaps and clinical workflow disruption.
If Mitigated
Isolated network segmentation prevents exploitation, maintaining device functionality with minimal impact.
🎯 Exploit Status
Exploitation requires only UDP packet crafting with no authentication, making it simple for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to Nihon Kohden security advisory for specific patched version
Restart Required: Yes
Instructions:
1. Contact Nihon Kohden support for firmware update 2. Schedule maintenance window 3. Apply firmware patch following vendor instructions 4. Reboot device 5. Verify functionality
🔧 Temporary Workarounds
Network Segmentation
allIsolate CNS-6201 devices on separate VLAN with strict firewall rules blocking unnecessary UDP traffic
Firewall UDP Restrictions
allBlock UDP packets to CNS-6201 from untrusted networks and limit to authorized monitoring stations only
🧯 If You Can't Patch
- Implement strict network segmentation to isolate CNS-6201 from general hospital network
- Deploy intrusion detection systems to monitor for UDP packet anomalies targeting medical devices
🔍 How to Verify
Check if Vulnerable:
Check device firmware version against Nihon Kohden's advisory. If running unpatched version, device is vulnerable.Check Version:
Check device system information menu or contact Nihon Kohden support for version verificationVerify Fix Applied:
Verify firmware version matches patched version in vendor advisory and test device functionality remains stable.📡 Detection & Monitoring
Log Indicators:
- Device crash logs
- Unexpected reboots
- UDP packet processing errors
Network Indicators:
- Unusual UDP traffic patterns to CNS-6201 devices
- Multiple UDP packets from single source
SIEM Query:
source_ip=* AND dest_port=* AND protocol=UDP AND dest_ip=CNS-6201_IP AND packet_size=anomalous🔗 References
- https://jvn.jp/en/vu/JVNVU96989989/
- https://www.nihonkohden.com/security.html
- https://www.cisa.gov/news-events/ics-medical-advisories/icsma-25-296-01
- https://www.nihonkohden.com/security/main/01112/teaserItems3/0/linkList/0/link/NKcorporateResponse-CNS-6201_CentralMonitor_Vulnerability(CVE-2025-59668)_en_Rev2.pdf
