CVE-2021-33884 in SpaceCom2
Summary
by MITRE • 08/25/2021
An Unrestricted Upload of File with Dangerous Type vulnerability in B. Braun SpaceCom2 prior to 012U000062 allows remote attackers to upload any files to the /tmp directory of the device through the webpage API. This can result in critical files being overwritten.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/29/2021
The vulnerability identified as CVE-2021-33884 represents a critical security flaw in B. Braun SpaceCom2 medical device software versions prior to 012U000062. This issue manifests as an unrestricted file upload vulnerability that allows remote attackers to bypass normal file validation mechanisms and place arbitrary files into the system's temporary directory at /tmp. The flaw exists within the web-based application programming interface that handles file operations, creating an attack surface where malicious actors can exploit the lack of proper input sanitization and access controls. The vulnerability is particularly concerning in healthcare environments where medical devices handle sensitive patient data and critical operational functions, as it could potentially lead to system compromise and unauthorized access to medical records or device controls.
The technical implementation of this vulnerability stems from inadequate validation of file types and upload paths within the SpaceCom2 device's web interface. When users submit files through the webpage API, the system fails to properly verify the file extensions, content types, or file contents before storing them in the /tmp directory. This absence of proper file validation creates a path traversal and arbitrary file upload condition that aligns with CWE-434, which specifically addresses unrestricted upload of file with dangerous type. The vulnerability allows attackers to upload executable files, scripts, or configuration files that could be executed by the system or used to overwrite critical system files, potentially leading to complete system compromise or denial of service conditions.
The operational impact of this vulnerability extends beyond simple unauthorized file placement, as it creates opportunities for attackers to manipulate the device's operational behavior and potentially access sensitive medical information. Remote exploitation of this vulnerability could enable attackers to overwrite critical system files, install backdoors, or execute malicious code within the device's environment. The /tmp directory access provides attackers with a persistent location to store malicious payloads that could survive system reboots or be used to establish footholds for further attacks. This vulnerability particularly affects healthcare organizations where medical devices are connected to hospital networks and may contain sensitive patient data, creating potential breaches that could violate HIPAA compliance requirements and expose patient privacy. The risk is amplified because medical devices often operate in isolated networks but may still require remote access for maintenance or updates, creating additional attack vectors.
Mitigation strategies for CVE-2021-33884 should prioritize immediate patching of affected B. Braun SpaceCom2 devices to version 012U000062 or later, which includes proper file validation and upload restrictions. Organizations should implement network segmentation to isolate medical devices from general network traffic and apply strict access controls to device interfaces. The remediation process should include disabling unnecessary web services, implementing proper file type validation, and restricting write permissions to the /tmp directory. Security controls should follow NIST SP 800-53 guidelines for secure configuration management, including regular vulnerability assessments and penetration testing of medical device networks. Additionally, organizations should implement network monitoring solutions that can detect anomalous file upload activities and establish incident response procedures specifically tailored for medical device security incidents. The vulnerability also highlights the importance of applying the principle of least privilege and following ATT&CK framework tactics for device security, particularly focusing on privilege escalation and persistence techniques that attackers might employ through such upload vulnerabilities.