Hi there.

Describe the bug
I am migrating a project from .Net Framework 4.7.2 to .NET 6.
And I am getting error in response when it is serialized.

System.ServiceModel.ProtocolException: There is a problem with the XML data received from the network. See the description of the inner exception for details. ---> System.Xml.XmlException: The data at the root level is invalid. Line 1, position 1.

I think this is due to the fact that the response does not support chunking.

I got response like this

20d
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><ns2:searchClientRs xmlns:ns2="........">
    <messageHeader>
        <messageId>689b1900-ef74-4352-90fd-d180d59c1a37</messageId>
        <correlationId>689b1900-ef74-4352-90fd-d180d59c1a37</correlationId>
        <responseStatus>
            <code>0</code>
            <textMessage/>
            <warning xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/>
        </responseStatus>
    </messageHead
33f
er>
    <clients>
        <client>
            <bankId>1</bankId>
...

Symbols "20d" and "33f" it's special symbol in chunked response, as far as I understand))

I tried using the TransferMode setting to enable chunking.
But neither the TransferMode.Stream setting nor the TransferMode.StreamResponse setting helped and returned the same error.

I found this code in source

namespace System.ServiceModel.Channels
{
    internal class HttpResponseMessageHelper
    {
    ...
        private Task<Message> ReadStreamAsMessageAsync(TimeoutHelper timeoutHelper)
        {
            var content = _httpResponseMessage.Content;
            Task<Stream> contentStreamTask = GetStreamAsync();
 
            if (TransferModeHelper.IsResponseStreamed(_factory.TransferMode))
            {
                return ReadStreamedMessageAsync(contentStreamTask);
            }
            if (!content.Headers.ContentLength.HasValue)
            {
                return ReadChunkedBufferedMessageAsync(contentStreamTask, timeoutHelper);
            }
            return ReadBufferedMessageAsync(contentStreamTask);
        }

And I checked all three read methods.
They all throw the same exception.

To Reproduce
I'm working with a SOAP service that I don't have access to and it's written in Java.
So I don't know how to reproduce this code.
I can attach the full text of the response with headers.

Expected behavior
I expect that everything will work just as well as on the .NET Framework 4.7.2.

Additional context
Soap UI correctly parses this response.