diff --git a/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/DefaultRazorDocumentMappingService.cs b/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/DefaultRazorDocumentMappingService.cs
index 07f5855fa60..1b883ebb8f5 100644
--- a/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/DefaultRazorDocumentMappingService.cs
+++ b/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/DefaultRazorDocumentMappingService.cs
@@ -637,6 +637,12 @@ private bool TryMapFromProjectedDocumentRangeInclusive(IRazorGeneratedDocument g
         originalRange = default;
 
         var csharpSourceText = GetGeneratedSourceText(generatedDocument);
+
+        if (!IsRangeWithinDocument(projectedRange, csharpSourceText))
+        {
+            return false;
+        }
+
         var projectedRangeAsSpan = projectedRange.AsTextSpan(csharpSourceText);
         var range = projectedRange;
         var startIndex = projectedRangeAsSpan.Start;