Siemens AG SINUMERIK 828D V4.7, SINUMERIK 840D sl V4.7, SINUMERIK 840D sl V4.8: Integer Overflow or Wraparound

A vulnerability has been identified in SINUMERIK 828D V4.7 (All versions < V4.7 SP6 HF1), SINUMERIK 840D sl V4.7 (All versions < V4.7 SP6 HF5), SINUMERIK 840D sl V4.8 (All versions < V4.8 SP3). The integrated VNC server on port 5900/tcp of the affected products could allow a remote attacker to execute code with privileged permissions on the system by sending specially crafted network requests to port 5900/tcp. Please note that this vulnerability is only exploitable if port 5900/tcp is manually opened in the firewall configuration of network port X130. The security vulnerability could be exploited by an attacker with network access to the affected devices and port. Successful exploitation requires no privileges and no user interaction. The vulnerability could allow an attacker to compromise confidentiality, integrity and availability of the VNC server. At the time of advisory publication no public exploitation of this security vulnerability was known.

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.