Siemens released new firmware to fix an improper access control vulnerability in its Ruggedcom ROS, SCALANCE lines, according to a report with ICS-CERT.
Successful exploitation of this vulnerability could allow users of networks adjacent to the targeted device to perform unauthorized administrative actions.
The remotely exploitable vulnerability, which Siemens self-reported, affects the following devices which use the Ruggedcom Discovery Protocol (RCDP):
• RUGGEDCOM ROS for RSL910 devices: All versions prior to ROS v5.0.1
• RUGGEDCOM ROS for all other devices: All versions prior to ROS v4.3.4
• SCALANCE XB-200/XC-200/XP-200/XR300-WG: All versions newer than v3.0
• SCALANCE XR-500/XM-400: All versions newer than v6.1
No known public exploits specifically target this vulnerability. However, an attacker with low skill level could leverage the vulnerability.
In the vulnerability, after initial configuration, the RCDP is still able to write to the device under certain conditions, potentially allowing users located in the adjacent network of the targeted device to perform unauthorized administrative actions.
CVE-2017-12736 is the case number assigned to this vulnerability, which has a CVSS v3 base score of 8.8.
The products see use mainly in the energy, transportation systems, healthcare and public health sectors. They also see action on a global basis.
Siemens provides Ruggedcom ROS firmware Version v4.3.4, v5.0.1 and Ruggedcom Explorer v1.5.2 which fixes the vulnerability and recommends users update to the newest version. The firmware updates for the Ruggedcom ROS-based devices can be obtained by emailing the Ruggedcom support team,
Siemens is preparing updates for the remaining affected products and recommends users manually deactivate RCDP according to the instructions in the user guide. Click here for the user guide on the Siemens web site.
As a general security measure, Siemens advises configuring the IT environment according to Siemens operational guidelines in order to run the devices in a protected manner.
For more information on these vulnerabilities and more detailed mitigation instructions, please see Siemens Security Advisory SSA-856721.