CVE-2018-17444 in SD-WAN
Summary
by MITRE
A Directory Traversal issue was discovered in Citrix SD-WAN 10.1.0 and NetScaler SD-WAN 9.3.x before 9.3.6 and 10.0.x before 10.0.4.
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Analysis
by VulDB Data Team • 04/06/2020
The vulnerability identified as CVE-2018-17444 represents a critical directory traversal flaw affecting Citrix SD-WAN and NetScaler SD-WAN products across multiple versions. This security weakness allows unauthorized users to access files and directories outside the intended scope of the application, potentially leading to sensitive data exposure and system compromise. The affected versions include Citrix SD-WAN 10.1.0 and NetScaler SD-WAN 9.3.x versions prior to 9.3.6, as well as 10.0.x versions before 10.0.4, indicating a widespread impact across different product lines and release cycles.
The technical implementation of this directory traversal vulnerability stems from inadequate input validation and sanitization within the web application interfaces of these SD-WAN solutions. Attackers can exploit this flaw by crafting malicious requests that contain directory traversal sequences such as ../ or ..\ in file path parameters. The vulnerability manifests when the application fails to properly validate user-supplied input before processing file access requests, allowing attackers to navigate beyond the intended directory structure and access restricted files on the underlying file system. This weakness falls under the CWE-22 category of "Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')" and aligns with ATT&CK technique T1083 for discovering files and directories.
The operational impact of this vulnerability extends beyond simple information disclosure, as it can enable attackers to access configuration files, authentication credentials, and other sensitive system data that may be stored in accessible locations. Organizations utilizing affected Citrix SD-WAN deployments face significant risk of unauthorized access to their network infrastructure management systems, potentially compromising the integrity and confidentiality of their entire SD-WAN ecosystem. The vulnerability's exploitation can lead to complete system compromise, data exfiltration, and disruption of critical network services that rely on these SD-WAN solutions for connectivity and traffic management.
Mitigation strategies for CVE-2018-17444 should prioritize immediate patching of affected systems to the latest available versions that contain the necessary security fixes. Organizations must also implement network segmentation and access controls to limit exposure of vulnerable components to untrusted networks. Additional protective measures include deploying web application firewalls to filter malicious path traversal attempts, implementing strict input validation and sanitization at all application interfaces, and conducting regular security assessments to identify and remediate similar vulnerabilities. Security monitoring should be enhanced to detect anomalous file access patterns that may indicate exploitation attempts, while incident response procedures should be updated to address potential compromise scenarios involving these critical network infrastructure components.