CVE-2016-5748 in Access Manager
Summary
by MITRE
External Entity Processing (XXE) vulnerability in the "risk score" application of NetIQ Access Manager 4.1 before 4.1.2 Hot Fix 1 and 4.2 before 4.2.2 could be used to disclose the content of local files to logged-in users.
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Analysis
by VulDB Data Team • 09/11/2020
The CVE-2016-5748 vulnerability represents a critical external entity processing flaw within NetIQ Access Manager's risk score application component. This vulnerability falls under the CWE-611 category of "Improper Restriction of XML External Entity Reference" and aligns with ATT&CK technique T1213.002 for Data from Information Repositories. The vulnerability exists in the XML parsing functionality that processes risk score requests, specifically when the application handles external entity references without proper sanitization or restriction mechanisms.
The technical implementation of this vulnerability allows authenticated attackers to craft malicious XML requests that reference local file paths through external entity declarations. When the risk score application processes these requests, it fails to properly validate or restrict external entity references, enabling an attacker to traverse the file system and retrieve sensitive local files. The vulnerability specifically affects versions prior to NetIQ Access Manager 4.1.2 Hot Fix 1 and 4.2.2, indicating that the vendor had identified and patched this issue in subsequent releases.
The operational impact of this vulnerability is significant as it enables information disclosure attacks that could expose sensitive system data, configuration files, or user information to authenticated users. Attackers could potentially access system logs, configuration files, credential storage locations, or other sensitive data that resides locally on the server. This creates a privilege escalation scenario where authenticated users can access data beyond their intended permissions, potentially leading to further compromise of the access management infrastructure.
The vulnerability demonstrates poor input validation practices in XML processing components and represents a failure to implement proper XML security controls. Organizations using affected versions should immediately apply the vendor-provided hot fixes or upgrade to supported versions. Mitigation strategies include implementing XML parser configurations that disable external entity processing, restricting XML schema validation, and deploying network segmentation controls to limit access to the affected application. Additionally, regular security assessments and input validation testing should be conducted to prevent similar vulnerabilities in other XML processing components within the infrastructure.