1 files changed, 10 insertions, 7 deletions
diff --git a/crypto/src/asn1/x9/X9ECParametersHolder.cs b/crypto/src/asn1/x9/X9ECParametersHolder.cs
index b3455709c..e802b738c 100644
--- a/crypto/src/asn1/x9/X9ECParametersHolder.cs
+++ b/crypto/src/asn1/x9/X9ECParametersHolder.cs
@@ -8,14 +8,17 @@ namespace Org.BouncyCastle.Asn1.X9
 		{
 			get
 			{
-				if (parameters == null)
-				{
-					parameters = CreateParameters();
-				}
+                lock (this)
+                {
+                    if (parameters == null)
+                    {
+                        parameters = CreateParameters();
+                    }
 
-				return parameters;
-			}
-		}
+                    return parameters;
+                }
+            }
+        }
 
 		protected abstract X9ECParameters CreateParameters();
 	}