Skip to content

Nihon Kohden CNS-6201 Central Monitor Vulnerability

Nihon Kohden monitor

Overview

A critical vulnerability in the Nihon Kohden CNS-6201 central monitoring system allows remote attackers to crash the system through malformed UDP packets, resulting in loss of patient monitoring capabilities.

Technical Specifications

Attribute Details
CVE ID CVE-2025-59668
Vulnerability Type NULL pointer dereference (CWE-476)
Attack Vector Network-based (UDP)
Authentication None required
CVSS Score High (Availability Impact)

Affected Versions

  • CNS-6201 software versions: 01-03, 01-04, 01-05, 01-06, 02-10, 02-11, and 02-40

Attack Scenario

  1. Attacker gains network access to medical device network
  2. Sends malformed UDP packet to CNS-6201's open UDP port
  3. Device attempts to dereference NULL pointer
  4. Software crashes, causing monitoring system unavailability
  5. Manual restart/reboot required to restore functionality

Impact Assessment

  • Central monitoring service crash
  • Temporary system unavailability
  • Requires manual intervention to restore
  • Loss of real-time patient data visualization
  • Interruption of alarm systems
  • Potential monitoring gaps during downtime
  • Manual restart procedures required
  • Operational workflow disruption
  • Need for backup monitoring protocols

Mitigation Strategies

Network Controls

  • Network Segmentation: Isolate CNS-6201 on secure medical network
  • Access Control: Restrict UDP communication to trusted devices only
  • Firewall Rules: Block malformed or unexpected UDP packets

Security Measures

  • Intrusion Detection: Deploy IDS to monitor for attack patterns
  • Traffic Filtering: Implement deep packet inspection for UDP traffic
  • Network Monitoring: Real-time monitoring of medical device communications

System Management

  • Upgrade Path: Migrate to supported models (CNS-9601, CNS-9101)
  • Incident Response: Implement automated restart procedures
  • Alarm Escalation: Verify backup alarm systems during downtime

Resources and References

Official Documentation

End-of-Support Notice

The affected CNS-6201 versions are end-of-support (EoS). Organizations should prioritize migration to supported models to ensure continued security updates and vendor support.