nssm.exe is a windows process. This executable file creates logs all progress in an Event log. nssm.exe is part of couchdb, which may cause anti-virus software to flag it as a third party file.
While this file could be removed, it is not recommended nor supported due to potential adverse affects in the software. We are looking to remove this entirely in the upcoming releases of ArcGIS Enterprise.
For more details, I would reach out to PSIRT
Keep on keeping on!