function issuerSigNToolToStr(rgExtension:PCERT_EXTENSION;cExtension:dword):string;
var     pExtension:PCERT_EXTENSION;
 cbStructInfo, i: Cardinal;
         pvStructInfo: Cardinal;
type   PIssuerSigNTool=^IssuerSigNTool;
       IssuerSigNTool = record
       sigNTool     :String[200];
       cATool       :string[200];
       signToolCert :String[100];
       cAToolCert   :String[100];
end;
  var szOID: LPSTR;
         ISNT:  pIssuerSigNTool;
begin
szOid:='1.2.643.100.112';
 pExtension := CertFindExtension(szOID,cExtension,rgExtension);

 if (Assigned(pExtension) and CryptDecodeObject(X509_ASN_ENCODING or PKCS_7_ASN_ENCODING, X509_ANY_STRING,
      pExtension^.Value.pbData, pExtension^.Value.cbData, 0, nil, @cbStructInfo)) then
  begin
   pvStructInfo := LocalAlloc(LMEM_FIXED, cbStructInfo);
   if pvStructInfo <> 0 then
    begin
     CryptDecodeObject(X509_ASN_ENCODING or PKCS_7_ASN_ENCODING, X509_ANY_STRING, pExtension^.Value.pbData,
                       pExtension^.Value.cbData, 0, Pointer(pvStructInfo), @cbStructInfo);

     ISNT := pIssuerSigNTool(pvStructInfo);
          result:=isnt.cATool+', '+isnt.cAToolCert+', '+isnt.sigNTool+', '+isnt.signToolCert;

    end;
     LocalFree(pvStructInfo);
  end;
end;

....
var size: dword;
 nameString: PChar;
 
szOid:='1.2.643.100.112';
 pExtension := CertFindExtension(szOID,cExtension,rgExtension);
 CryptBinaryToString(pExtension^.Value.pbData, pExtension^.Value.cbData,CRYPT_STRING_BINARY,nil,size);
 if size > 1 then
 begin
 nameString := StrAlloc(size);
 CryptBinaryToString(pExtension^.Value.pbData, pExtension^.Value.cbData,CRYPT_STRING_BINARY,namestring,size);
end;

type        PCRYPT_DER_BLOB = array of CRYPT_DER_BLOB;
var     pExtension:PCERT_EXTENSION;   
 cbStructInfo, i: Cardinal;
pvStructInfo: Cardinal;
szOID: LPSTR;
CSOA: PCRYPT_SEQUENCE_OF_ANY;
        F: PCRYPT_DER_BLOB;
begin
szOid:='1.2.643.100.112';
pExtension := CertFindExtension(szOID,cExtension,rgExtension);  
 if (Assigned(pExtension) and CryptDecodeObject(X509_ASN_ENCODING or PKCS_7_ASN_ENCODING, X509_SEQUENCE_OF_ANY,
      pExtension^.Value.pbData, pExtension^.Value.cbData, 0, nil, @cbStructInfo)) then
  begin
   pvStructInfo := LocalAlloc(LMEM_FIXED, cbStructInfo);
   if pvStructInfo <> 0 then
    begin
     CryptDecodeObject(X509_ASN_ENCODING or PKCS_7_ASN_ENCODING, X509_SEQUENCE_OF_ANY, pExtension^.Value.pbData,
                       pExtension^.Value.cbData, 0, pointer(pvStructInfo), @cbStructInfo);

       CSOA := PCRYPT_SEQUENCE_OF_ANY(pvStructInfo);
     f:=PCRYPT_DER_BLOB(CSOA.rgValue);
     IssuerSigNTool.sigNTool:=ByteArrayToUTF8(f[0].pbData,f[0].cbData);
      IssuerSigNTool.cATool:=ByteArrayToUTF8(f[1].pbData,f[1].cbData);
      IssuerSigNTool.signToolCert:=ByteArrayToUTF8(f[2].pbData,f[2].cbData);
     IssuerSigNTool.cAToolCert:=ByteArrayToUTF8(f[3].pbData,f[3].cbData);
.....
function ByteArrayToUTF8(pbData: PByte; cbData: DWORD): String;
type PByteArray = ^TByteArray;
   TByteArray = Array[0..32767] of Byte;
var
I: Integer;
S: String;
begin
Result := '';
if not Assigned(pbData) or (cbData <= 0) then
Exit;
for I := cbData - 1 downto 2 do
begin
S := chr(PByteArray(pbData)^[i]);
Result := S + Result
end;
end;