CVE-2021-33885: B. Braun SpaceCom2 RCE Vulnerability

CVE-2021-33885 Overview

CVE-2021-33885 is an Insufficient Verification of Data Authenticity vulnerability affecting B. Braun SpaceCom2 medical infusion pump systems. This critical flaw allows a remote unauthenticated attacker to send malicious data to the device that will be used in place of legitimate data. The vulnerability exists due to the lack of cryptographic signatures on critical data sets, ultimately resulting in full system command access and execution capabilities for attackers.

This vulnerability is particularly concerning given its presence in medical devices used in healthcare settings worldwide. The ability for an unauthenticated remote attacker to gain full system command access on infusion pump systems represents a significant patient safety risk.

Critical Impact

Remote unauthenticated attackers can achieve full system command access and execution on B. Braun infusion pump systems by exploiting the lack of cryptographic signature verification on critical data, potentially compromising patient safety in healthcare environments.

Affected Products

• B. Braun SpaceCom2 (prior to version 012U000062)
• B. Braun Infusomat Large Volume Pump (871305U)
• B. Braun SpaceStation (8713142U)

Discovery Timeline

• 2021-08-25 - CVE-2021-33885 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2021-33885

Vulnerability Analysis

The vulnerability stems from a fundamental design flaw in how the B. Braun SpaceCom2 communication module handles incoming data. The system fails to properly verify the authenticity of data it receives, allowing an attacker to inject malicious payloads that the device will accept and process as legitimate commands.

This insufficient verification of data authenticity (CWE-347) means the device lacks proper cryptographic mechanisms to validate that incoming data originates from a trusted source and has not been tampered with. Without cryptographic signatures on critical data sets, the device has no way to distinguish between legitimate operational commands and malicious instructions crafted by an attacker.

The network-accessible nature of these medical devices makes them particularly vulnerable, as attackers on the same network segment or with network access can directly communicate with the infusion pump systems.

Root Cause

The root cause of CVE-2021-33885 is the absence of cryptographic signature verification mechanisms for critical data processed by the SpaceCom2 communication module. The device accepts and processes incoming data without validating its authenticity or integrity through digital signatures, message authentication codes (MACs), or other cryptographic verification methods. This architectural deficiency means the system inherently trusts any data it receives, regardless of source.

Attack Vector

The attack vector is network-based, requiring no authentication or user interaction. An attacker with network access to the affected B. Braun devices can exploit this vulnerability by:

1. Identifying target SpaceCom2 devices on the network
2. Crafting malicious data packets that mimic legitimate device communications
3. Transmitting the malicious data to the target device
4. The device processes the attacker-controlled data as authentic
5. Achieving full system command access and execution capabilities

The lack of authentication requirements significantly lowers the barrier to exploitation, as attackers do not need to compromise credentials or establish a trusted session before launching an attack.

The vulnerability mechanism involves the device's failure to validate cryptographic signatures on incoming data. An attacker can craft malicious payloads that the SpaceCom2 module will accept and execute as legitimate commands. For detailed technical analysis, see the McAfee Enterprise ATR vulnerability analysis.

Detection Methods for CVE-2021-33885

Indicators of Compromise

• Unexpected network traffic patterns to/from SpaceCom2 devices from unauthorized IP addresses
• Anomalous command sequences or configuration changes on infusion pump systems
• Unauthorized modifications to drug libraries or dosing parameters
• System logs showing command execution from unexpected sources
• Network communications lacking proper authentication handshakes

Detection Strategies

• Implement network traffic analysis to identify unusual communication patterns with medical devices
• Deploy intrusion detection systems (IDS) with rules specific to medical device protocols
• Monitor for unauthorized access attempts to SpaceCom2 management interfaces
• Establish baseline behavior profiles for infusion pump network communications and alert on deviations

Monitoring Recommendations

• Continuously monitor network segments containing B. Braun infusion pump systems
• Implement logging and alerting for all administrative actions on affected devices
• Deploy network segmentation monitoring to detect lateral movement toward medical device VLANs
• Review device logs regularly for signs of unauthorized command execution or configuration changes

How to Mitigate CVE-2021-33885

Immediate Actions Required

• Update B. Braun SpaceCom2 devices to firmware version 012U000062 or later immediately
• Isolate affected medical devices on dedicated network segments with strict access controls
• Implement firewall rules to restrict network access to infusion pump systems to authorized endpoints only
• Conduct an inventory of all B. Braun infusion pump systems to identify vulnerable devices

Patch Information

B. Braun has released firmware version 012U000062 for the SpaceCom2 module that addresses this vulnerability. Healthcare organizations should coordinate with B. Braun or authorized service providers to apply the security update to all affected devices. Given the critical nature of medical devices, patching should be performed following established clinical engineering change management procedures.

For additional information, visit the B. Braun USA website for official security advisories and support resources.

Workarounds

• Implement strict network segmentation to isolate medical devices from general network traffic
• Deploy application-layer firewalls to filter and inspect traffic to/from infusion pump systems
• Disable unnecessary network services and ports on affected devices where possible
• Implement network access control (NAC) to restrict which systems can communicate with medical devices
• Consider deploying network monitoring solutions specifically designed for medical device environments

# Example network segmentation firewall rules (adjust for your environment)
# Restrict SpaceCom2 device access to authorized management stations only

# Block all inbound traffic to medical device VLAN by default
iptables -A FORWARD -d 10.10.50.0/24 -j DROP

# Allow specific authorized management station
iptables -A FORWARD -s 10.10.100.50 -d 10.10.50.0/24 -j ACCEPT

# Allow necessary clinical systems (adjust IPs as needed)
iptables -A FORWARD -s 10.10.100.0/24 -d 10.10.50.0/24 -p tcp --dport 443 -j ACCEPT

# Log dropped packets for monitoring
iptables -A FORWARD -d 10.10.50.0/24 -j LOG --log-prefix "MedDevice-Blocked: "