Siemens has a new version out to mitigate an improper input validation vulnerability in its SIMATIC TDC CP51M1, according to a report with CISA.
Successful exploitation of this remotely exploitable vulnerability, which Siemens self-reported, could create a denial-of-service condition within UDP communication.
A multiprocessor automation system, all versions of SIMATIC TDC CP51M1 prior to 1.1.7 suffer from the issue. In the vulnerability, an attacker sending a specially crafted UDP packet to the device may affect the UDP communication, causing a denial-of-service condition.
CVE-2019-10937 is the case number assigned to this vulnerability, which has a CVSS v3 base score of 7.5.
The product sees use mainly in the critical manufacturing sector. It also sees action on a global basis.
No known public exploits specifically target this vulnerability. However, an attacker with low skill level could leverage the vulnerability.
Siemens recommends users update to Version 1.1.7 or later.
Siemens has identified the following specific workarounds and mitigations that users may apply to reduce the risk:
• Restrict network access to affected devices
• Restrict UDP communication to affected devices
• Do not use UDP communication in the user program if not needed
• Apply cell protection concept and implement defense in depth
As a general security measure, Siemens recommends users protect network access to devices with appropriate mechanisms.
In order to operate the devices in a protected IT environment, Siemens recommends users configure the environment according to Siemens’ operational guidelines for industrial security, and follow the recommendations in the product manuals.
Click here for additional information on industrial security by Siemens.
For more information, see Siemens Security Advisory SSA-250618.