I saw these lines on my server log:
/samples/winnt/system32/cmd.exe?/c+dir HTTP Response 302
/scripts/winnt/system32/cmd.exe?/c+dir HTTP Response 302
/cgi-bin/winnt/system32/cmd.exe?/c+dir HTTP Response 302
/vti_bin/winnt/system32/cmd.exe?/c+dir HTTP Response 302
/samples/winnt/system32/cmd.exe?/c+dir HTTP Response 302
/vti_cnf/winnt/system32/cmd.exe?/c+dir HTTP Response 302
/vti_bin/winnt/system32/cmd.exe?/c+dir HTTP Response 302
Apparently, a bad guy was trying to probe on old vulnerabilities of IIS. The bad guy was not very professional. He should have performed web server OS fingerprinting before launching the probe.