ICSA-17-045-03 Siemens SIMATIC Authentication Bypass (Update D)

An authentication bypass vulnerability exists in Siemens SIMATIC Logon and related HMI/automation products. The flaw allows an attacker on the network to bypass user authentication mechanisms and gain unauthorized access to SIMATIC engineering interfaces and HMI systems without valid credentials. Affected products include SIMATIC Logon, WinCC (both standard and Runtime Professional), PCS 7, PDM, and SIMATIC IT Production Suite. The vulnerability is a CWE-592 issue (authentication bypass). An attacker exploiting this could access process control logic, modify setpoints, change recipes, or disrupt production operations. Siemens has released patches for all affected product lines. Note that SIMATIC Logon updates can be installed independently of other component updates in many cases.