certmgr -inst -store uMy -file ./cert.cer -cont '\\.\HDIMAGE\536baf7a'

LibCore.Initializer.Initialize(
LibCore.Initializer.DetouredAssembly.Xml |
LibCore.Initializer.DetouredAssembly.Pkcs |
LibCore.Initializer.DetouredAssembly.X509Certificates |
LibCore.Initializer.DetouredAssembly.Algorithms |
LibCore.Initializer.DetouredAssembly.Csp);

using var myStore = new CpX509Store(StoreName.My);
myStore.Open(OpenFlags.ReadOnly);

var certColl = myStore.Certificates.Find(X509FindType.FindByThumbprint, certificateSerial, false);
var certificate = certColl[0];

var bytes = Encoding.UTF8.GetBytes(dataToSign);

var contentInfo = new ContentInfo(bytes);
var signedCms = new SignedCms(contentInfo, true);
var cmsSigner = new CmsSigner(certificate);
cmsSigner.SignedAttributes.Add(new Pkcs9SigningTime(DateTime.Now));

signedCms.ComputeSignature(cmsSigner);

var signature = signedCms.Encode();

signedCms.ComputeSignature(cmsSigner)

Crypto-Pro GOST R 34.10-2012 KC1 CSP requests container password