diff --git a/src/libraries/System.Net.Http/src/System/Net/Http/BrowserHttpHandler/BrowserHttpHandler.cs b/src/libraries/System.Net.Http/src/System/Net/Http/BrowserHttpHandler/BrowserHttpHandler.cs
index b4450bb425641..c187e80d15f90 100644
--- a/src/libraries/System.Net.Http/src/System/Net/Http/BrowserHttpHandler/BrowserHttpHandler.cs
+++ b/src/libraries/System.Net.Http/src/System/Net/Http/BrowserHttpHandler/BrowserHttpHandler.cs
@@ -220,7 +220,6 @@ protected internal override async Task<HttpResponseMessage> SendAsync(HttpReques
                     requestObject.SetObjectProperty("headers", jsHeaders);
                 }
 
-
                 WasmHttpReadStream? wasmHttpReadStream = null;
 
                 JSObject abortController = new HostObject("AbortController");
@@ -375,6 +374,12 @@ public void Dispose()
             }
         }
 
+        private sealed class BrowserUnseekableStream : MemoryStream
+        {
+            public BrowserUnseekableStream (byte [] data) : base (data, writable: false) { }
+            public override bool CanSeek => false;
+        }
+
         private sealed class BrowserHttpContent : HttpContent
         {
             private byte[]? _data;
@@ -407,7 +412,7 @@ private async Task<byte[]> GetResponseData()
             protected override async Task<Stream> CreateContentReadStreamAsync()
             {
                 byte[] data = await GetResponseData().ConfigureAwait(continueOnCapturedContext: true);
-                return new MemoryStream(data, writable: false);
+                return new BrowserUnseekableStream (data);
             }
 
             protected override Task SerializeToStreamAsync(Stream stream, TransportContext? context) =>