CVE-2019-25720: Dräger SC Monitoring DOS Vulnerability

CVE-2019-25720 Overview

CVE-2019-25720 is a denial-of-service vulnerability affecting Dräger SC Monitoring devices, including the SC 6002XL, SC 6802XL, SC 7000, SC 8000, and SC 9000 XL patient monitors. An unauthenticated attacker on the adjacent network can send a malformed network packet that forces the monitor to reboot. Repeated transmission of these packets disrupts patient monitoring and eventually causes the device to fall back to its default configuration, losing network connectivity in the process. The flaw exists in all software versions of the affected product line and is categorized under [CWE-1286] for improper validation of syntactic correctness of input.

Critical Impact

Repeated malformed packets disrupt continuous patient monitoring and force affected devices off the hospital network.

Affected Products

• Dräger SC 6002XL, SC 6802XL Patient Monitors (all software versions)
• Dräger SC 7000, SC 8000 Patient Monitors (all software versions)
• Dräger SC 9000 XL Patient Monitor (all software versions)

Discovery Timeline

• 2026-06-03 - CVE-2019-25720 published to NVD
• 2026-06-03 - Last updated in NVD database

Technical Details for CVE-2019-25720

Vulnerability Analysis

The Dräger SC family of patient monitors fails to properly validate the structure of incoming network packets. When the device receives a malformed packet on its network interface, the input parsing logic does not handle the syntactic error gracefully. Instead, the monitor enters a fault state and reboots. The condition is reachable without authentication, requiring only adjacent network access to the device. An attacker with access to the same clinical network segment can trigger the reboot loop on demand.

Root Cause

The root cause is improper validation of syntactic correctness of input [CWE-1286]. The network stack on the monitor accepts packets that do not conform to expected protocol structure and propagates the malformed data into processing routines that cannot tolerate it. Because the parser does not enforce strict input validation, a single crafted packet is sufficient to crash the runtime.

Attack Vector

Exploitation occurs over an adjacent network. The attacker must be able to reach the monitor's network interface, typically by gaining a foothold on the hospital LAN or a connected clinical VLAN. No credentials, user interaction, or prior privilege on the device is required. By scripting repeated delivery of the malformed packet, the attacker can keep the monitor in a continuous reboot cycle. After repeated reboots, affected SC monitors revert to default configuration and lose their network connection, severing the device from central monitoring stations.

No verified proof-of-concept code is published. For technical specifics, refer to the Dräger Security Advisory Update and the VulnCheck Advisory.

Detection Methods for CVE-2019-25720

Indicators of Compromise

• Unexpected reboots of SC 6002XL, SC 6802XL, SC 7000, SC 8000, or SC 9000 XL monitors without a clinical or maintenance cause.
• SC monitors reverting to default configuration and dropping off the central monitoring network.
• Bursts of malformed or non-conforming packets directed at patient monitor IP addresses on clinical VLANs.

Detection Strategies

• Deploy passive medical-device-aware network monitoring on clinical VLANs to flag protocol anomalies targeting SC monitor IP ranges.
• Correlate device reboot events from the Dräger central station with concurrent network packet anomalies on the same segment.
• Alert when a previously enrolled SC monitor returns to factory-default network settings, which indicates it has cycled through repeated failures.

Monitoring Recommendations

• Maintain an inventory of all SC series monitor IP addresses and baseline expected traffic patterns.
• Log and review all source hosts initiating connections to patient monitor network segments.
• Configure SIEM correlation rules to flag repeated short-interval reboot events across multiple monitors as a potential coordinated attack.

How to Mitigate CVE-2019-25720

Immediate Actions Required

• Segment all SC monitors onto isolated clinical VLANs that block traffic from general-purpose user and guest networks.
• Restrict access to monitor network interfaces using switch port ACLs and 802.1X authentication where supported.
• Verify that the Dräger central monitoring station alerts on lost connectivity so reboot-induced outages are detected immediately.

Patch Information

Dräger has issued a security advisory covering this vulnerability. Operators should consult the Dräger Security Advisory Update for vendor-recommended firmware and network configuration guidance. Contact Dräger service representatives for the latest mitigations applicable to specific monitor models and software revisions.

Workarounds

• Place SC monitors behind a firewall that permits only required protocols and source addresses for the central monitoring system.
• Disable or physically isolate unused network ports on the monitor where operationally feasible.
• Implement strict ingress filtering at the clinical network boundary to drop malformed or non-conforming packets before they reach medical devices.

# Configuration example
# Example: restrict access to SC monitor VLAN at a network ACL
# Permit only the central monitoring server to reach monitors on TCP/UDP service ports.
access-list SC_MONITORS permit ip host 10.10.20.5 10.10.30.0 0.0.0.255
access-list SC_MONITORS deny   ip any 10.10.30.0 0.0.0.255 log
access-list SC_MONITORS permit ip any any
interface Vlan30
 description Patient-Monitoring-SC-Series
 ip access-group SC_MONITORS in