VBScript
openssl smime -encrypt -des3 -in <file> <pem file>

OpenSSL SMIME encrypt file using PEM containing a certificate.
Chilkat VBScript Downloads

VBScript
Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

success = 0

' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' Load the cert from a PEM file.

set pem = CreateObject("Chilkat.Pem")
' Our particular PEM was not encrypted, so we pass an empty password.
' Also, a private key is not needed for encryption.  The PEM used to test this example
' happens to have a private key, but it's not actually used.
success = pem.LoadPemFile("qa_data/openssl/rsaCertAndKey.pem","")
If (success = 0) Then
    outFile.WriteLine(pem.LastErrorText)
    WScript.Quit
End If

If (pem.NumCerts = 0) Then
    outFile.WriteLine("PEM does not contain any certificates.")
    WScript.Quit
End If

' cert is a Chilkat.Cert
Set cert = pem.GetCert(0)
If (pem.LastMethodSuccess = 0) Then
    outFile.WriteLine(pem.LastErrorText)
    WScript.Quit
End If

' -------------------------------------------------------------------------------------
' Duplicate this OpenSSL command:   openssl smime -encrypt -des3 -in <file> <pem file>
' -------------------------------------------------------------------------------------
set crypt = CreateObject("Chilkat.Crypt2")
success = crypt.SetEncryptCert(cert)
If (success = 0) Then
    outFile.WriteLine(crypt.LastErrorText)

    WScript.Quit
End If

crypt.CryptAlgorithm = "PKI"
crypt.Pkcs7CryptAlg = "3des"
crypt.KeyLength = 168

' Load the file to be encrypted.
set bd = CreateObject("Chilkat.BinData")
success = bd.LoadFile("qa_data/openssl/hello.txt")
If (success = 0) Then
    outFile.WriteLine("Failed to load the input file.")
    WScript.Quit
End If

' Encrypt.
success = crypt.EncryptBd(bd)
If (success = 0) Then
    outFile.WriteLine(crypt.LastErrorText)
    WScript.Quit
End If

' The openssl smime -encrypt command produces encrypte MIME such as this:

' MIME-Version: 1.0
' Content-Disposition: attachment; filename="smime.p7m"
' Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name="smime.p7m"
' Content-Transfer-Encoding: base64
' 
' MIICzwYJKoZIhvcNAQcDoIICwDCCArwCAQAxggF8MIIBeAIBADBgMEoxCzAJBgNVBAYTAlVTMRYw
' FAYDVQQKEw1MZXQncyBFbmNyeXB0MSMwIQYDVQQDExpMZXQncyBFbmNyeXB0IEF1dGhvcml0eSBY
' MwISA9Nqgb1dH/XTDNeKzN1nR85iMA0GCSqGSIb3DQEBAQUABIIBAIQqPexjxWovgxwKV/r3HL/U
' EP9Yozvz5hBeX5VvRZjKSi4FRw5wapElPK+4FB82hiAR9Mi3c16PvPSVkJv3l78Mv5uaaOs/OmUz
' mIHFB6Z+l2E52BDmUVWJZTQ09vdWy6+NIRlg2R9Z1NkmZ4BZCJk6mHB/Yx03IaOxK8LnwieDMthM
' SvxbhJnIOISN7k7ofs+/0vTXUpdQ+tlmwyVySMGQ6VMk+z4sqZJ2stacqCPtt/aiSwJ9p0OKmihf
' 3KDJceXJtavIQeA97yz1LqPvle35mmd5sBhV9qQYdTV/KJ+YM5uEZ9BHYbvMJbADFHwKzhcEY3qA
' 7T9acmEsb7NycOIwggE1BgkqhkiG9w0BBwEwFAYIKoZIhvcNAwcECERX/ZoHweSkgIIBEMmCMx49
' zjVAnGqRaBbvzQT1hg0uQSxIJjxMxC+HSuM+eY9oSOsbrw4uIijHKH9NdOpeDsdRzg2z5EBM7AlP
' Ht9DyPW5C2deV6RPX4F8gyExz+JUXrd+3Yb3AKTdpDkTWDmNCeO0r/YSqp518+mfU5hG8e336u51
' HAM44FeknA8oThWsD/wUB1e8vzsatK4UXW/KSu/166V7z+VT86kd+IHa7t60U9Yp0ZXgcM5Pb5Ni
' 69Qc5MKPzom2801H5UR/WjCgsxOIjOj49sKisjRy79skrJzxY5ZG05T0dKn6KC3TjRpIEEeOyhCd
' Nm2Y7dcW8GLMepdhWay5vePmQxmvmhbAtBprIem14NcrYeG6D5wP

' We have the body in bd
' Construct the header and base64 body...
set sbEncryptedMime = CreateObject("Chilkat.StringBuilder")

success = sbEncryptedMime.AppendLine("MIME-Version: 1.0",1)
success = sbEncryptedMime.AppendLine("Content-Disposition: attachment; filename=""smime.p7m""",1)
success = sbEncryptedMime.AppendLine("Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name=""smime.p7m""",1)
success = sbEncryptedMime.AppendLine("Content-Transfer-Encoding: base64",1)
success = sbEncryptedMime.AppendLine("",1)
success = sbEncryptedMime.AppendLine(bd.GetEncoded("base64_mime"),1)

' Show the result.
outFile.WriteLine(sbEncryptedMime.GetAsString())

' or save to a file..
success = sbEncryptedMime.WriteFile("qa_output/encryptedMime.txt","utf-8",0)

outFile.Close