CVE-2019-20049 in OmniVista 4760
Summary
by MITRE
An issue was discovered on Alcatel-Lucent OmniVista 4760 devices. A remote unauthenticated attacker can chain a directory traversal (which helps to bypass authentication) with an insecure file upload to achieve Remote Code Execution as SYSTEM. The directory traversal is in the __construct() whereas the insecure file upload is in SetSkinImages().
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Analysis
by VulDB Data Team • 03/18/2024
The vulnerability CVE-2019-20049 represents a critical security flaw affecting Alcatel-Lucent OmniVista 4760 network management devices that combines multiple exploitation vectors to achieve unauthorized remote code execution with SYSTEM privileges. This vulnerability demonstrates a sophisticated attack pattern that leverages both authentication bypass capabilities and insecure file handling to compromise the targeted network infrastructure. The flaw exists within the device's web-based management interface, making it accessible to remote attackers without requiring valid credentials or prior access to the network.
The technical implementation of this vulnerability involves two primary attack vectors that work in conjunction to achieve the final exploitation outcome. The directory traversal vulnerability specifically affects the __construct() method within the application's codebase, allowing attackers to manipulate file paths and bypass the authentication mechanisms that should normally protect access to sensitive system functions. This directory traversal flaw enables an attacker to access restricted directories and files that would typically be protected from unauthorized access. The second component involves an insecure file upload vulnerability located in the SetSkinImages() function, which permits attackers to upload malicious files to the system without proper validation or sanitization of the uploaded content.
The operational impact of this vulnerability extends beyond simple unauthorized access, as successful exploitation results in complete system compromise with SYSTEM level privileges. This means that an attacker who successfully exploits this vulnerability can execute arbitrary code on the target device with the highest level of system permissions, effectively gaining full control over the network management system. The implications are particularly severe for network infrastructure management devices, as these systems often serve as central points of control for network operations and may have access to sensitive network configurations, user credentials, and operational data. The combination of these vulnerabilities creates a pathway for attackers to establish persistent access to the network management infrastructure while remaining undetected by normal security monitoring systems.
Security practitioners should consider this vulnerability in the context of the MITRE ATT&CK framework, particularly focusing on the techniques related to privilege escalation, command and control communications, and credential access. The vulnerability aligns with CWE-22 (Directory Traversal) and CWE-434 (Insecure Upload of Critical Data) classifications, which together represent a dangerous combination of weaknesses that can be exploited to achieve complete system compromise. Organizations should implement immediate mitigations including network segmentation to isolate management interfaces, deployment of web application firewalls to detect and block malicious file upload attempts, and mandatory firmware updates from the vendor to address the identified vulnerabilities. Additionally, regular security assessments should be conducted to identify similar vulnerabilities in other network management systems and ensure that proper input validation and access control mechanisms are in place to prevent similar exploitation patterns from occurring in the future.