CVE-2015-4594 in Population Health
Summary
by MITRE
eClinicalWorks Population Health (CCMR) suffers from a session fixation vulnerability. When authenticating a user, the application does not assign a new session ID, making it possible to use an existent session ID.
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Analysis
by VulDB Data Team • 04/20/2025
The vulnerability identified as CVE-2015-4594 affects eClinicalWorks Population Health Clinical Case Management Reporter (CCMR) software, representing a critical session fixation weakness that undermines the application's authentication security model. This flaw resides in the session management implementation where the system fails to properly handle session identifier rotation during user authentication processes, creating a persistent security risk that can be exploited by malicious actors to hijack user sessions.
The technical flaw manifests when users authenticate to the CCMR application, as the system does not generate a new session identifier upon successful login. Instead, it maintains the existing session ID that may have been established during a previous interaction or even an attacker-controlled session. This behavior directly violates established security best practices for session management and creates an environment where an attacker who has previously established a session can reuse the same session identifier to impersonate legitimate users. The vulnerability stems from inadequate session handling mechanisms that fail to implement proper session regeneration after authentication events.
From an operational perspective, this session fixation vulnerability presents significant risks to healthcare organizations utilizing eClinicalWorks CCMR systems. Attackers can exploit this weakness to gain unauthorized access to patient health records, clinical case data, and other sensitive information within the population health management platform. The impact extends beyond simple unauthorized access as it can enable persistent surveillance of user activities, data manipulation, and potential privilege escalation within the healthcare information system. The vulnerability is particularly concerning in healthcare environments where data protection regulations such as hipaa mandate strict controls over patient information access and authentication processes.
The security implications of this vulnerability align with CWE-384, which specifically addresses session fixation issues in applications where session identifiers are not properly regenerated after authentication. This weakness can be leveraged through various attack vectors including man-in-the-middle techniques, cross-site scripting attacks, or direct session interception methods that allow adversaries to obtain valid session tokens. The attack surface is further expanded when considering that healthcare systems often have limited network segmentation and may lack robust monitoring capabilities for detecting session hijacking attempts. Organizations should implement comprehensive session management policies that enforce session regeneration upon authentication and implement additional security controls such as session timeout mechanisms, secure cookie attributes, and proper session validation procedures to mitigate this risk effectively.
Mitigation strategies for CVE-2015-4594 should include immediate patching of the affected eClinicalWorks CCMR software to address the session fixation vulnerability, implementation of proper session regeneration protocols during authentication events, and deployment of additional security controls such as secure session cookie flags, session timeout configurations, and network monitoring to detect suspicious session behavior. Organizations should also consider implementing multi-factor authentication mechanisms and regular security assessments to identify and remediate similar vulnerabilities within their healthcare information systems. The remediation process must ensure that all session identifiers are properly regenerated upon successful authentication and that the application enforces strict session management policies that prevent session fixation attacks from succeeding.