diff --git a/src/libraries/Common/src/System/Security/Cryptography/Asn1/DirectoryStringAsn.xml.cs b/src/libraries/Common/src/System/Security/Cryptography/Asn1/DirectoryStringAsn.xml.cs
index 7310045bca4dea..2f420f8cc5c9a4 100644
--- a/src/libraries/Common/src/System/Security/Cryptography/Asn1/DirectoryStringAsn.xml.cs
+++ b/src/libraries/Common/src/System/Security/Cryptography/Asn1/DirectoryStringAsn.xml.cs
@@ -2,13 +2,13 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 #pragma warning disable SA1028 // ignore whitespace warnings for generated code
 using System;
 using System.Runtime.InteropServices;
 using System.Security.Cryptography;
 using System.Security.Cryptography.Asn1;
 
-#nullable enable
 namespace System.Security.Cryptography.Asn1
 {
     [StructLayout(LayoutKind.Sequential)]
diff --git a/src/libraries/Common/src/System/Security/Cryptography/Asn1/GeneralNameAsn.xml.cs b/src/libraries/Common/src/System/Security/Cryptography/Asn1/GeneralNameAsn.xml.cs
index dfd311632120fd..79316b126f8e9d 100644
--- a/src/libraries/Common/src/System/Security/Cryptography/Asn1/GeneralNameAsn.xml.cs
+++ b/src/libraries/Common/src/System/Security/Cryptography/Asn1/GeneralNameAsn.xml.cs
@@ -2,13 +2,13 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 #pragma warning disable SA1028 // ignore whitespace warnings for generated code
 using System;
 using System.Runtime.InteropServices;
 using System.Security.Cryptography;
 using System.Security.Cryptography.Asn1;
 
-#nullable enable
 namespace System.Security.Cryptography.Asn1
 {
     [StructLayout(LayoutKind.Sequential)]
diff --git a/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.OSX.cs b/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.OSX.cs
index 99440d90665051..2802eade16633a 100644
--- a/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.OSX.cs
+++ b/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.OSX.cs
@@ -3,7 +3,6 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
-using System.Collections.Generic;
 using System.Security.Cryptography;
 using System.Security.Cryptography.Asn1;
 using System.Text;
@@ -25,7 +24,7 @@ internal class AppleAsnFormatter : AsnFormatter
         {
             if (oid == null || string.IsNullOrEmpty(oid.Value))
             {
-                return EncodeHexString(rawData, true);
+                return EncodeSpaceSeparatedHexString(rawData);
             }
 
             switch (oid.Value)
diff --git a/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.cs b/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.cs
index 2ac6572cbd0cbc..54f508e3df5c27 100644
--- a/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.cs
+++ b/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/AsnFormatter.cs
@@ -3,7 +3,7 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
-using System.Diagnostics.CodeAnalysis;
+using System.Diagnostics;
 using System.Security.Cryptography;
 
 namespace Internal.Cryptography
@@ -19,31 +19,19 @@ public string Format(Oid? oid, byte[] rawData, bool multiLine)
 
         protected abstract string? FormatNative(Oid? oid, byte[] rawData, bool multiLine);
 
-        protected static string EncodeHexString(byte[] sArray, bool spaceSeparated = false)
+        protected static string EncodeSpaceSeparatedHexString(byte[] sArray)
         {
-            return EncodeHexString(sArray, 0, (uint)sArray.Length, spaceSeparated);
-        }
+            Debug.Assert(sArray != null && sArray.Length != 0);
 
-        [return: NotNullIfNotNull("sArray")]
-        private static string? EncodeHexString(byte[]? sArray, uint start, uint end, bool spaceSeparated)
-        {
-            string? result = null;
+            int length = (sArray.Length * 3) - 1; // two chars per byte, plus 1 space between each
 
-            if (sArray != null)
+            return string.Create(length, sArray, (hexOrder, sArray) =>
             {
-                uint len = (end - start) * 2;
+                int j = 0;
 
-                if (spaceSeparated)
+                for (int i = 0; i < sArray.Length; i++)
                 {
-                    // There will be n-1 spaces between n bytes.
-                    len += (end - start - 1);
-                }
-
-                char[] hexOrder = new char[len];
-
-                for (uint i = start, j = 0; i < end; i++)
-                {
-                    if (spaceSeparated && i > start)
+                    if (i != 0)
                     {
                         hexOrder[j++] = ' ';
                     }
@@ -53,10 +41,8 @@ protected static string EncodeHexString(byte[] sArray, bool spaceSeparated = fal
                     hexOrder[j++] = HexConverter.ToCharUpper(digit);
                 }
 
-                result = new string(hexOrder);
-            }
-
-            return result;
+                Debug.Assert(j == hexOrder.Length);
+            });
         }
     }
 }
diff --git a/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/OpenSslAsnFormatter.cs b/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/OpenSslAsnFormatter.cs
index 063d036aa86efc..c39484dd866b40 100644
--- a/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/OpenSslAsnFormatter.cs
+++ b/src/libraries/System.Security.Cryptography.Encoding/src/Internal/Cryptography/OpenSslAsnFormatter.cs
@@ -2,7 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
 using System.Security.Cryptography;
 using System.Text;
 
@@ -16,7 +15,7 @@ internal sealed class OpenSslAsnFormatter : AsnFormatter
         {
             if (oid == null || string.IsNullOrEmpty(oid.Value))
             {
-                return EncodeHexString(rawData, true);
+                return EncodeSpaceSeparatedHexString(rawData);
             }
 
             // The established behavior for this method is to return the native answer, if possible,