CVE-2015-0931 in Ektron CMS
Summary
by MITRE
Ektron Content Management System (CMS) 8.5 and 8.7 before 8.7sp2 and 9.0 before sp1, when the Saxon XSLT parser is used, allows remote attackers to execute arbitrary code via a crafted XSLT document, related to a "resource injection" issue.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 11/04/2024
The vulnerability identified as CVE-2015-0931 affects the Ektron Content Management System versions 8.5 and 8.7 before 8.7sp2 and 9.0 before sp1 when utilizing the Saxon XSLT parser. This represents a critical security flaw that enables remote attackers to execute arbitrary code on affected systems. The vulnerability stems from improper handling of resource loading within the XSLT processing pipeline, creating an environment where malicious actors can inject and execute unauthorized code through specially crafted XSLT documents. The issue specifically manifests when the system processes external resources referenced within XSLT transformations, allowing attackers to manipulate the resource resolution mechanism to load and execute malicious content.
The technical exploitation of this vulnerability involves leveraging a resource injection flaw within the Saxon XSLT parser implementation used by Ektron CMS. When the system processes XSLT documents that contain references to external resources, the parser fails to properly validate or sanitize these resource identifiers. This allows attackers to craft XSLT documents that reference malicious external resources, potentially including remote files or local system paths that can be manipulated to execute arbitrary commands. The vulnerability operates at the intersection of XML processing and resource management, creating a path for code execution that bypasses normal security controls. This type of vulnerability is classified under CWE-20 as "Improper Input Validation" and specifically relates to CWE-94 as "Improper Control of Generation of Code ('Code Injection')" within the context of XSLT processing.
The operational impact of this vulnerability is severe and multifaceted, potentially allowing complete system compromise and unauthorized access to sensitive data. Remote attackers can leverage this vulnerability to execute arbitrary code with the privileges of the affected web application, which typically runs with elevated permissions on the server. This could result in full system compromise, data exfiltration, persistence mechanisms establishment, and lateral movement within the network infrastructure. The vulnerability affects organizations using Ektron CMS in production environments where content management systems are accessible over the internet, making them prime targets for exploitation. Attackers can exploit this vulnerability to gain unauthorized access to corporate content, user data, and potentially use the compromised system as a foothold for further attacks. The impact extends beyond immediate code execution to include potential denial of service conditions, data corruption, and unauthorized modification of content managed through the CMS.
Organizations should prioritize immediate remediation by applying the vendor-provided patches for Ektron CMS versions 8.7sp2 and 9.0sp1, which address the resource injection vulnerability in the Saxon XSLT parser. System administrators should also implement network segmentation and access controls to limit exposure of CMS systems to untrusted networks. Additional mitigations include disabling external resource loading in XSLT processing where possible, implementing strict input validation for all XSLT documents, and monitoring system logs for suspicious resource access patterns. Security teams should also consider implementing web application firewalls to detect and block malicious XSLT content and establish regular vulnerability scanning procedures. The ATT&CK framework categorizes this vulnerability under T1059 for Command and Scripting Interpreter and T1068 for Exploitation for Privilege Escalation, highlighting the potential for both code execution and privilege escalation attacks. Organizations should also consider implementing security awareness training for content managers and developers who work with XSLT documents to prevent accidental introduction of vulnerable code into production environments.