A vulnerability has been identified in SCALANCE X-200 switch family (incl. SIPLUS NET variants) (All versions < V5.2.3), SCALANCE X-200IRT switch family (incl. SIPLUS NET variants) (All versions < V5.4.1), SCALANCE X-200RNA switch family (All versions < V3.2.7), SCALANCE X-300 switch family (incl. X408 and SIPLUS NET variants) (All versions < V4.1.3). The integrated configuration web server of the affected devices could allow Cross-Site Scripting (XSS) attacks if unsuspecting users are tricked into accessing a malicious link. User interaction is required for a successful exploitation. The user must be logged into the web interface in order for the exploitation to succeed. At the stage of publishing this security advisory no public exploitation is known. The vendor has confirmed the vulnerability and provides mitigations to resolve it.

The authentication implementation in the web server on Siemens SCALANCE X-200 switches with firmware before 5.0.0 does not use a sufficient source of entropy for generating values of random numbers, which makes it easier for remote attackers to hijack sessions by predicting a value.