GE has an update available to mitigate a path traversal vulnerability in its Mark VIe, EX2100e, EX2100e_Reg, and LS2100e, according to a report with NCCIC.
Successful exploitation of this vulnerability, discovered by Can Demirel of Biznet Bilisim, could allow an attacker to access system data, which could result in escalation of privilege and unauthorized access to the controller.
A distributed control system , the following versions of the Mark Vie suffer from the vulnerability:
• Mark VIe Versions 03.03.28C to 05.02.04C
• EX2100e All versions prior to v04.09.00C
• EX2100e_Reg All versions prior to v04.09.00C
• LS2100e All versions prior to v04.09.00C
The affected versions of the application have a path traversal vulnerability that fails to restrict the ability of an attacker to gain access to restricted information.
CVE-2018-19003 is the case number assigned to this vulnerability, which has a CVSS v3 base score of 7.4.
The product sees use mainly in the energy sector. It also sees action on a global basis.
No known public exploits specifically target this vulnerability. This vulnerability is not exploitable remotely. However, an attacker with low skill level could leverage the vulnerability.
The path traversal vulnerability has been corrected by GE. GE recommends users upgrade to the current version of ControlST software as described in CSB25378, which is available to registered users via the GE Power ServiceNow portal.
In applications where the controller-hosted web server is not required, GE recommends turning off the web server. For all other applications, GE recommends updating the controller to the latest firmware version available in the current ControlST release.
With respect to EX2100e, GE recommends all standalone excitation controls be segmented from other networks using a firewall installed inside the excitation panels. External communication should be exclusively restricted to only those protocols specifically required for command and control, such as Modbus. Other services including HTTP must be blocked from external access.
To minimize the risk of exposure to this and any other vulnerabilities, GE recommends a defense-in-depth approach to protecting critical process control equipment. Guidance on technology and best practices to secure GE controllers from cyber attack are provided in the Mark VIe Control Systems Secure Deployment Guide (GEH-6839), which can be requested through GE Technical Support.
Additionally, GE recommends users of affected versions take the following mitigating actions while awaiting an upgrade:
• Maintain tight physical access control to all critical controllers
• Limit network availability to only the most critical needs and implement tight firewall restrictions
• Disable any unnecessary network related functions or enable only on an as needed basis
GE provides additional up to date information concerning this issue (requires customer account/login).
Or contact GE PSIRT.