CVE-2018-4067 in AirLink ES450
Summary
by MITRE
An exploitable information disclosure vulnerability exists in the ACEManager template_load.cgi functionality of Sierra Wireless AirLink ES450 FW 4.9.3. A specially crafted HTTP request can cause a information leak, resulting in the disclosure of internal paths and files. An attacker can make an authenticated HTTP request to trigger this vulnerability.
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Analysis
by VulDB Data Team • 09/12/2023
The vulnerability identified as CVE-2018-4067 represents a critical information disclosure flaw within the Sierra Wireless AirLink ES450 firmware version 4.9.3. This issue manifests through the ACEManager template_load.cgi component which handles template loading functionality. The vulnerability stems from insufficient input validation and output sanitization within the web application interface, creating an exploitable condition that allows unauthorized information exposure. The affected device operates as a cellular gateway and network management appliance, making it a prime target for attackers seeking to gather system intelligence for further exploitation attempts. The flaw specifically affects the template loading mechanism that processes HTTP requests containing specially crafted parameters designed to trigger directory traversal behaviors.
The technical implementation of this vulnerability involves the template_load.cgi script failing to properly validate user-supplied input parameters before processing them in file system operations. When an authenticated user submits a malicious HTTP request containing crafted parameters, the system's inadequate sanitization allows for directory traversal sequences to be executed within the file system context. This results in the exposure of internal file paths, system directories, and potentially sensitive configuration files that should remain hidden from external access. The vulnerability operates at the application layer and requires authentication to exploit, indicating a privilege escalation vector that could be leveraged by authenticated attackers or those who have obtained valid credentials through other means. This aligns with CWE-200, which categorizes information exposure vulnerabilities where insufficient controls lead to unauthorized information disclosure.
The operational impact of this vulnerability extends beyond simple information disclosure as it provides attackers with critical system intelligence that can be used for subsequent attacks. The leaked internal paths and file structures enable attackers to understand the system architecture, potentially identifying other vulnerable components or services running on the device. This information disclosure creates opportunities for attackers to craft more sophisticated attacks against the device's web interface or underlying operating system. The vulnerability affects network management appliances that are often deployed in critical infrastructure environments, making the exposure of internal system information particularly concerning. Attackers can leverage this information to plan targeted attacks against the device's firmware or other connected systems within the network segment. The presence of this vulnerability in a cellular gateway device also raises concerns about potential escalation to broader network compromise or denial of service conditions.
Mitigation strategies for CVE-2018-4067 should focus on immediate firmware updates from Sierra Wireless to address the underlying validation flaws in the template_load.cgi functionality. Network administrators should implement strict access controls and authentication measures to limit who can make requests to the affected component. The implementation of web application firewalls and input validation rules can help prevent malformed requests from reaching the vulnerable component. Additionally, regular security assessments and penetration testing should be conducted to identify similar vulnerabilities in other network management devices. The vulnerability demonstrates the importance of proper input validation and output encoding in web applications, principles that align with the ATT&CK framework's mitigation strategies for information gathering and credential access phases. Organizations should also consider network segmentation to limit the potential impact of successful exploitation and implement monitoring solutions to detect unusual patterns of requests to web interfaces that might indicate exploitation attempts.