A vulnerability has been identified in SCALANCE M875 (All versions). The web interface on port 443/tcp could allow a stored Cross-Site Scripting (XSS) attack if an unsuspecting user is tricked into accessing a malicious link. Successful exploitation requires that the attacker has access to the web interface of an affected device. The attacker must be authenticated as administrative user on the web interface. Afterwards, a legitimate user must access the web interface. A successful attack could allow an attacker to execute malicious code in the browser of a legitimate user. At the time of advisory publication no public exploitation of this security vulnerability was known.
https://cert-portal.siemens.com/productcert/pdf/ssa-977428.pdf