CVE-2015-7924 in Device
Summary
by MITRE
eWON devices with firmware before 10.1s0 do not trigger the discarding of browser session data in response to a log-off action, which makes it easier for remote attackers to obtain access by leveraging an unattended workstation.
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Analysis
by VulDB Data Team • 05/20/2018
The vulnerability identified as CVE-2015-7924 affects eWON industrial devices running firmware versions prior to 10.1s0, presenting a significant security weakness in session management protocols. This flaw resides in the authentication and session handling mechanisms of these industrial communication devices, which are commonly deployed in critical infrastructure environments for remote monitoring and control applications. The vulnerability specifically manifests when users log out of the device's web interface, as the system fails to properly clear browser session data and cookies that may contain sensitive authentication tokens or session identifiers.
The technical implementation of this vulnerability stems from inadequate session cleanup procedures within the web server component of the eWON devices. When a user performs a log-off action, the device should trigger an immediate invalidation of session tokens and removal of all session-related data from the browser cache and memory. However, the affected firmware versions do not properly execute this cleanup process, leaving session artifacts accessible to subsequent users who might access the same workstation. This behavior creates a persistent security risk where unauthorized individuals can potentially exploit cached session information to gain unauthorized access to the device's administrative interface without requiring legitimate credentials.
The operational impact of this vulnerability extends beyond simple access control violations, as it fundamentally undermines the security posture of industrial environments where these devices are deployed. In scenarios where workstations are left unattended, particularly in manufacturing facilities, control rooms, or remote monitoring stations, the vulnerability becomes particularly dangerous. An attacker who gains physical access to an unattended workstation can exploit this weakness to access the device's management interface, potentially leading to unauthorized configuration changes, data exfiltration, or even disruption of industrial processes. This risk is exacerbated in environments where multiple operators share workstations or where devices are accessed from public or shared computing environments.
The vulnerability aligns with CWE-613, which addresses insufficient session expiration, and represents a classic example of poor session management practices that can be exploited through session hijacking techniques. From an adversarial perspective, this weakness maps to several ATT&CK techniques including T1078 Valid Accounts for maintaining persistent access and T1566 Phishing for initial compromise, as attackers can leverage cached session data to bypass authentication mechanisms. The risk is particularly elevated in industrial control systems where unauthorized access could lead to operational technology disruptions, safety hazards, or data integrity compromises.
Organizations should implement immediate mitigations including firmware updates to version 10.1s0 or later, which address the session cleanup vulnerability through proper invalidation of session tokens upon log-off events. Additionally, network segmentation strategies should be implemented to limit direct access to these devices, and access controls should be enforced through multi-factor authentication mechanisms. Regular security assessments should verify that session management functions operate correctly and that cached session data is properly cleared during log-off procedures. Administrative procedures should also include mandatory workstation lock policies and regular security training to prevent unauthorized access to devices through unattended workstations.