A vulnerability has been identified in DIGSI 4 (All versions < V4.94 SP1 HF 1). Several folders in the %PATH% are writeable by normal users. As these folders are included in the search for dlls, an attacker could place dlls there with code executed by SYSTEM.
https://us-cert.cisa.gov/ics/advisories/icsa-21-040-10
https://cert-portal.siemens.com/productcert/pdf/ssa-536315.pdf