csrss.exe is a program which is most likely NOT a virus or malware. So, if csrss.exe is on your PC, it is most likely ok, and will NOT be a cause for concern. Even if your PC is virus-free, it is still recommended to use a good antivirus with a good detection rate, in order to yourself your system against viruses and malware.
The default name and folder where the application is stored is
The MD5 fingerprint for this file is 4e043fe41901f1ea1b0fccef3c077c56.
This application is NOT registered as a Windows service. This is good.
csrss.exe appears to use the functions of Windows SFC (System File Checker) or Windows File Protection.
64-bit code has been detected. This exe can exploit the full power of a modern computer processor.
csrss.exe has a digital signature. Today the large majority of legit programs are digitally signed.
The digital signature attached to csrss.exe is valid. This is very good.
Digitally signed by: Microsoft Windows Publisher
Certificate's issuer name: Microsoft Windows Production PCA 2011
This program does NOT have an uninstall command stored in registry.