CVE-2018-19612 in DR-250 Pre-5162
Summary
by MITRE
The /uploadfile? functionality in Westermo DR-250 Pre-5162 and DR-260 Pre-5162 routers allows remote users to upload malicious file types and execute ASP code.
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Analysis
by VulDB Data Team • 09/24/2023
The vulnerability identified as CVE-2018-19612 affects Westermo DR-250 and DR-260 routers running firmware versions prior to 5162. This issue resides within the uploadfile functionality of the device's web interface, creating a critical security gap that enables remote attackers to bypass normal file validation mechanisms. The affected routers are industrial network devices commonly deployed in critical infrastructure environments, making this vulnerability particularly concerning from a cybersecurity perspective. The vulnerability stems from insufficient input validation and sanitization within the file upload handler, allowing malicious actors to upload files with potentially harmful content.
The technical flaw manifests through the lack of proper file type checking and content validation in the uploadfile endpoint. Attackers can exploit this weakness by uploading files with.asp extensions or other executable scripts that the router will process and execute. This vulnerability represents a classic case of insecure file upload handling, which maps directly to CWE-434 Unrestricted Upload of File with Dangerous Type. The implementation fails to properly validate file extensions, content type headers, or file signatures, allowing arbitrary code execution through the web server component of the router's firmware. The vulnerability exists at the application layer where user-supplied data is not adequately sanitized before being processed by the system.
The operational impact of this vulnerability is severe and multifaceted, particularly in industrial control systems and critical infrastructure environments. Remote code execution capabilities allow attackers to gain full control over the affected routers, potentially enabling them to modify network configurations, redirect traffic, or establish persistent backdoors. The vulnerability can be exploited without authentication, making it especially dangerous as it allows attackers to compromise network infrastructure from external locations. This threat vector aligns with ATT&CK technique T1059.007 Command and Scripting Interpreter: Visual Basic, as attackers can leverage the ASP execution capability to run malicious code. The compromised routers could serve as entry points for lateral movement within industrial networks, potentially affecting operational technology systems and disrupting critical processes.
Mitigation strategies should focus on immediate firmware updates to versions 5162 or later, which contain the necessary patches to address the file upload validation issues. Network administrators should also implement additional security controls including firewall rules that restrict access to the router's web management interface, network segmentation to limit the attack surface, and monitoring for suspicious file upload activities. The vulnerability demonstrates the importance of proper input validation and the principle of least privilege in network device security. Organizations should conduct comprehensive vulnerability assessments of their industrial control systems to identify similar issues in other network equipment. Implementing web application firewalls and regular security audits can help detect and prevent exploitation attempts. The incident highlights the critical need for secure coding practices in embedded systems and the importance of regular firmware updates in maintaining network security posture.