diff --git a/src/Microsoft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/InvokeRestMethodCommand.Common.cs b/src/Microsoft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/InvokeRestMethodCommand.Common.cs
index 0559e35daa..90abdf78bb 100644
--- a/src/Microsoft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/InvokeRestMethodCommand.Common.cs
+++ b/src/Microsoft.PowerShell.Commands.Utility/commands/utility/WebCmdlet/Common/InvokeRestMethodCommand.Common.cs
@@ -133,6 +133,7 @@ namespace Microsoft.PowerShell.Commands
             xrs.IgnoreProcessingInstructions = true;
             xrs.MaxCharactersFromEntities = 1024;
             xrs.DtdProcessing = DtdProcessing.Ignore;
+            xrs.XmlResolver = null;
 
             return xrs;
         }
diff --git a/src/Microsoft.PowerShell.ConsoleHost/host/msh/Serialization.cs b/src/Microsoft.PowerShell.ConsoleHost/host/msh/Serialization.cs
index abcd4ff2cf..f73c26107f 100644
--- a/src/Microsoft.PowerShell.ConsoleHost/host/msh/Serialization.cs
+++ b/src/Microsoft.PowerShell.ConsoleHost/host/msh/Serialization.cs
@@ -197,7 +197,7 @@ namespace Microsoft.PowerShell
             switch (format)
             {
                 case DataFormat.XML:
-                    _xmlReader = XmlReader.Create(textReader);
+                    _xmlReader = XmlReader.Create(textReader,  new XmlReaderSettings { XmlResolver = null });
                     _xmlDeserializer = new Deserializer(_xmlReader);
                     break;
                 case DataFormat.Text:
diff --git a/src/Microsoft.PowerShell.Security/security/CertificateProvider.cs b/src/Microsoft.PowerShell.Security/security/CertificateProvider.cs
index b8bcee8bd4..dc84f9a3b4 100644
--- a/src/Microsoft.PowerShell.Security/security/CertificateProvider.cs
+++ b/src/Microsoft.PowerShell.Security/security/CertificateProvider.cs
@@ -2876,9 +2876,7 @@ namespace Microsoft.PowerShell.Commands
                     currentUICulture.ToString(),
                     this.ProviderInfo.HelpFile);
                 XmlReaderSettings settings = new XmlReaderSettings();
-#if !CORECLR
                 settings.XmlResolver = null;
-#endif
                 using (XmlReader reader = XmlReader.Create(fullHelpPath, settings))
                 {
                     document.Load(reader);
diff --git a/src/Microsoft.PowerShell.Workflow.ServiceCore/ServiceCore/WorkflowCore/WorkflowRuntimeCompilation.cs b/src/Microsoft.PowerShell.Workflow.ServiceCore/ServiceCore/WorkflowCore/WorkflowRuntimeCompilation.cs
index 2ef5dce6d6..0955fa66e6 100644
--- a/src/Microsoft.PowerShell.Workflow.ServiceCore/ServiceCore/WorkflowCore/WorkflowRuntimeCompilation.cs
+++ b/src/Microsoft.PowerShell.Workflow.ServiceCore/ServiceCore/WorkflowCore/WorkflowRuntimeCompilation.cs
@@ -135,7 +135,7 @@ namespace Microsoft.PowerShell.Workflow
                 {
                     project.AddItem("XamlAppDef", file);
 
-                    XamlXmlReader reader = new XamlXmlReader(XmlReader.Create(file), new XamlSchemaContext());
+                    XamlXmlReader reader = new XamlXmlReader(XmlReader.Create(file, new XmlReaderSettings { XmlResolver = null }), new XamlSchemaContext());
                     using (reader)
                     {
                         while (reader.Read())
diff --git a/src/System.Management.Automation/engine/TypeTable.cs b/src/System.Management.Automation/engine/TypeTable.cs
index 41ae3c93f9..57ded79b28 100644
--- a/src/System.Management.Automation/engine/TypeTable.cs
+++ b/src/System.Management.Automation/engine/TypeTable.cs
@@ -4178,7 +4178,7 @@ namespace System.Management.Automation.Runspaces
             {
 #if CORECLR
                 // In OneCore powershell, XmlTextReader is not in CoreCLR, so we have to use XmlReader.Create method
-                XmlReader reader = XmlReader.Create(xmlStream, new XmlReaderSettings { IgnoreWhitespace = true });
+                XmlReader reader = XmlReader.Create(xmlStream, new XmlReaderSettings { IgnoreWhitespace = true, XmlResolver = null });
 #else
                 // In Full powershell, we create a XmlTextReader, so loadContext.reader is guaranteed to implement IXmlLineInfo
                 XmlReader reader = new XmlTextReader(xmlStream) { WhitespaceHandling = WhitespaceHandling.Significant };
diff --git a/src/System.Management.Automation/engine/remoting/fanin/OutOfProcTransportManager.cs b/src/System.Management.Automation/engine/remoting/fanin/OutOfProcTransportManager.cs
index 90a5be4cf0..be46f4532d 100644
--- a/src/System.Management.Automation/engine/remoting/fanin/OutOfProcTransportManager.cs
+++ b/src/System.Management.Automation/engine/remoting/fanin/OutOfProcTransportManager.cs
@@ -65,9 +65,7 @@ namespace System.Management.Automation.Remoting
             XmlReaderSettings.CheckCharacters = false;
             XmlReaderSettings.IgnoreComments = true;
             XmlReaderSettings.IgnoreProcessingInstructions = true;
-#if !CORECLR  // No XmlReaderSettings.XmlResolver in CoreCLR
             XmlReaderSettings.XmlResolver = null;
-#endif
             XmlReaderSettings.ConformanceLevel = ConformanceLevel.Fragment;
         }
 
diff --git a/src/System.Management.Automation/engine/remoting/fanin/PSSessionConfigurationData.cs b/src/System.Management.Automation/engine/remoting/fanin/PSSessionConfigurationData.cs
index 4b11b4472d..fd480daf58 100644
--- a/src/System.Management.Automation/engine/remoting/fanin/PSSessionConfigurationData.cs
+++ b/src/System.Management.Automation/engine/remoting/fanin/PSSessionConfigurationData.cs
@@ -89,9 +89,7 @@ namespace System.Management.Automation.Remoting
                 IgnoreComments = true,
                 IgnoreProcessingInstructions = true,
                 MaxCharactersInDocument = 10000,
-#if !CORECLR // No XmlReaderSettings.XmlResolver in CoreCLR
                 XmlResolver = null,
-#endif
                 ConformanceLevel = ConformanceLevel.Fragment
             };
 
diff --git a/src/System.Management.Automation/engine/serialization.cs b/src/System.Management.Automation/engine/serialization.cs
index b1a223bf00..716b8eb695 100644
--- a/src/System.Management.Automation/engine/serialization.cs
+++ b/src/System.Management.Automation/engine/serialization.cs
@@ -4026,15 +4026,11 @@ namespace System.Management.Automation
             xrs.IgnoreProcessingInstructions = true;
             xrs.IgnoreWhitespace = false;
             xrs.MaxCharactersFromEntities = 1024;
-            //xrs.DtdProcessing = DtdProcessing.Prohibit; //because system.management.automation needs to build as 2.0
-            //xrs.ProhibitDtd = true;
-#if !CORECLR
-            // XmlReaderSettings.Schemas/ValidationFlags/ValidationType/XmlResolver Not In CoreCLR
+            xrs.XmlResolver = null;
+            xrs.DtdProcessing = DtdProcessing.Prohibit;
             xrs.Schemas = null;
             xrs.ValidationFlags = System.Xml.Schema.XmlSchemaValidationFlags.None;
             xrs.ValidationType = ValidationType.None;
-            xrs.XmlResolver = null;
-#endif
             return xrs;
         }
 
@@ -4051,15 +4047,10 @@ namespace System.Management.Automation
             settings.IgnoreWhitespace = true;
             settings.MaxCharactersFromEntities = 1024;
             settings.MaxCharactersInDocument = 512 * 1024 * 1024; // 512M characters = 1GB
-
-#if CORECLR // DtdProcessing.Parse Not In CoreCLR
-            settings.DtdProcessing = DtdProcessing.Ignore;
-#else       // XmlReaderSettings.ValidationFlags/ValidationType/XmlResolver Not In CoreCLR
+            settings.XmlResolver = null;
             settings.DtdProcessing = DtdProcessing.Parse;   // Allowing DTD parsing with limits of MaxCharactersFromEntities/MaxCharactersInDocument
             settings.ValidationFlags = System.Xml.Schema.XmlSchemaValidationFlags.None;
             settings.ValidationType = ValidationType.None;
-            settings.XmlResolver = null;
-#endif
             return settings;
         }