--- com/itextpdf/signatures/PdfPKCS7.java.orig	2016-05-02 16:35:28.000000000 +0700
+++ com/itextpdf/signatures/PdfPKCS7.java	2016-07-31 21:57:34.952349000 +0700
@@ -622,6 +622,12 @@ public class PdfPKCS7 {
             else if (digestEncryptionAlgorithm.equals("ECDSA")) {
                 this.digestEncryptionAlgorithmOid = SecurityIDs.ID_ECDSA;
             }
+            else if (digestEncryptionAlgorithm.equals("GOST3410")) {
+                this.digestEncryptionAlgorithmOid = SecurityIDs.ID_GOST3410;
+            }
+            else if (digestEncryptionAlgorithm.equals("ECGOST3410")) {
+                this.digestEncryptionAlgorithmOid = SecurityIDs.ID_ECGOST3410;
+            }
             else
                 throw new PdfException(PdfException.UnknownKeyAlgorithm1).setMessageParams(digestEncryptionAlgorithm);
         }