CVE-2018-6442 in Fabric OS
Summary
by MITRE
A vulnerability in the Brocade Webtools firmware update section of Brocade Fabric OS before 8.2.1, 8.1.2f, 8.0.2f, 7.4.2d could allow remote authenticated attackers to execute arbitrary commands.
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Analysis
by VulDB Data Team • 04/11/2020
The vulnerability identified as CVE-2018-6442 represents a critical command injection flaw within the Brocade Webtools firmware update functionality of Brocade Fabric OS versions prior to 8.2.1, 8.1.2f, 8.0.2f, and 7.4.2d. This security weakness resides in the web-based management interface component that handles firmware updates, creating a pathway for malicious actors to execute unauthorized code on affected systems. The vulnerability specifically affects the authentication mechanisms and input validation processes within the firmware update section, allowing attackers who have already established legitimate credentials to escalate their privileges and gain arbitrary command execution capabilities. This flaw fundamentally undermines the security posture of Brocade fabric switches and fabric managers, as it provides a direct avenue for attackers to bypass normal access controls and execute system-level commands.
The technical exploitation of this vulnerability stems from inadequate input sanitization and validation within the firmware update web interface. When authenticated users interact with the firmware update functionality, the system fails to properly validate or sanitize user-supplied parameters that are subsequently processed by the underlying operating system. This lack of proper input validation creates a command injection vector where maliciously crafted input can be interpreted and executed as system commands rather than being treated as simple data. The vulnerability is classified as a command injection flaw under CWE-77, which specifically addresses situations where user-controllable data is passed to system commands without proper sanitization, making it particularly dangerous for network infrastructure devices that typically require elevated privileges to operate. Attackers can leverage this weakness to execute arbitrary code with the privileges of the web application process, potentially leading to complete system compromise and unauthorized access to the entire fabric network.
The operational impact of CVE-2018-6442 extends beyond simple privilege escalation, as it enables attackers to gain full control over affected Brocade fabric switches and fabric managers. This remote authenticated command execution capability allows adversaries to perform various malicious activities including but not limited to data exfiltration, network reconnaissance, disruption of fabric services, and establishment of persistent backdoors. The vulnerability is particularly concerning in enterprise environments where Brocade switches serve as critical network infrastructure components, as successful exploitation can lead to widespread network disruption and potential data breaches. Network administrators face significant challenges in detecting and mitigating this vulnerability since the attack appears to originate from legitimate authenticated users, making it difficult to distinguish between authorized and malicious activities within network monitoring systems. The impact is further compounded by the fact that the vulnerability affects multiple major versions of Brocade Fabric OS, indicating a widespread exposure across various network deployments.
Organizations affected by CVE-2018-6442 should prioritize immediate remediation through firmware updates to versions 8.2.1, 8.1.2f, 8.0.2f, or 7.4.2d, respectively, as these releases contain the necessary patches to address the command injection vulnerability. Network security teams should implement comprehensive monitoring of web application logs and network traffic for suspicious command execution patterns, particularly in the firmware update sections of affected systems. The vulnerability aligns with ATT&CK technique T1059.001 for command and scripting interpreter, as attackers can leverage the system's command execution capabilities to perform various malicious activities. Additionally, implementing network segmentation and access controls to limit the scope of potential exploitation, combined with regular security assessments of web-based management interfaces, can help reduce the overall risk exposure. Organizations should also consider implementing additional security controls such as web application firewalls and privileged access management solutions to provide defense-in-depth against similar vulnerabilities in their network infrastructure components.