Reload SP2 file (WEXTRACT.EXE)

My anti-virus sofware (F-Secure) detected the Trojan-Dropper virus in two files and could not disinfect them. It renamed the files so they could not be used. The files are:

C:\\Windows\System32\WEXTRACT.EXE

C:\\Windows\ServicePack Files\I386\WEXTRACT.EXE

 

Windows asked me to insert the SP2 CD but I downloaded SP2 and have no CD.

 

Is there a way to reload these files without having to deinstall/reinstall SP2? Is a SP2 CD available?