smss.exe is a program which is most likely NOT a virus or malware. So, if smss.exe is on your system, it is most likely ok, and will NOT be a cause for concern. Even if your PC is virus-free, we still advise you to use a good antivirus with a good detection rate, in order to yourself your PC against viruses and malware.
This program is normally stored in C:\Windows\System32\smss.exe.
The MD5 checksum for this file is 03ce2ba7d96391aea2bfd935d243260f.
This program is NOT a Windows service. This is very good.
smss.exe seems to use the functions of Windows SFC (System File Checker) or Windows File Protection.
This is a x64 executable. It uses the full capacity of nowadays' CPUs.
smss.exe has a digital signature. Today most serious software applications are digitally signed.
The digital signature found in smss.exe verifies as ok. This is very good.
Digitally signed by: Microsoft Windows Publisher
Certificate's issuer name: Microsoft Windows Production PCA 2011
This executable does NOT have an uninstall routine stored in registry.