diff --git a/OpenMcdf.Tests/StreamExtensions.cs b/OpenMcdf.Tests/StreamExtensions.cs
index a370949..341ec1a 100644
--- a/OpenMcdf.Tests/StreamExtensions.cs
+++ b/OpenMcdf.Tests/StreamExtensions.cs
@@ -1,7 +1,27 @@
-namespace OpenMcdf.Tests;
+#if !NET7_0_OR_GREATER
+using System.Buffers;
+#endif
+
+namespace OpenMcdf.Tests;
 
 internal static class StreamExtensions
 {
+#if !NET7_0_OR_GREATER
+    public static void ReadExactly(this Stream stream, Span<byte> buffer)
+    {
+        byte[] array = ArrayPool<byte>.Shared.Rent(buffer.Length);
+        try
+        {
+            stream.ReadExactly(array, 0, buffer.Length);
+            array.AsSpan(0, buffer.Length).CopyTo(buffer);
+        }
+        finally
+        {
+            ArrayPool<byte>.Shared.Return(array);
+        }
+    }
+#endif
+
     public static void Write(this Stream stream, byte[] buffer, WriteMode mode)
     {
 #if (!NETSTANDARD2_0 && !NETFRAMEWORK)
diff --git a/OpenMcdf/CfbBinaryReader.cs b/OpenMcdf/CfbBinaryReader.cs
index 354a07b..0f0b3d0 100644
--- a/OpenMcdf/CfbBinaryReader.cs
+++ b/OpenMcdf/CfbBinaryReader.cs
@@ -1,10 +1,6 @@
 using System.Diagnostics;
 using System.Text;
 
-#if NETSTANDARD2_0
-using System.Buffers;
-#endif
-
 namespace OpenMcdf;
 
 /// <summary>
@@ -26,37 +22,11 @@ public long Position
         set => BaseStream.Position = value;
     }
 
-#if NETSTANDARD2_0
-
-    public int Read(Span<byte> buffer)
-    {
-        byte[] array = ArrayPool<byte>.Shared.Rent(buffer.Length);
-        try
-        {
-            int bytesRead = BaseStream.Read(array, 0, buffer.Length);
-            array.AsSpan(0, bytesRead).CopyTo(buffer);
-            return bytesRead;
-        }
-        finally
-        {
-            ArrayPool<byte>.Shared.Return(array);
-        }
-    }
-
-#endif
-
     void ReadExactly(byte[] buffer, int offset, int count) => BaseStream.ReadExactly(buffer, offset, count);
 
     public Guid ReadGuid()
     {
-        int bytesRead = 0;
-        do
-        {
-            int n = Read(guidBuffer, bytesRead, guidBuffer.Length - bytesRead);
-            if (n == 0)
-                throw new EndOfStreamException();
-            bytesRead += n;
-        } while (bytesRead < guidBuffer.Length);
+        BaseStream.ReadExactly(guidBuffer, 0, guidBuffer.Length);
 
         return new Guid(guidBuffer);
     }
diff --git a/OpenMcdf/Fat.cs b/OpenMcdf/Fat.cs
index 6c8ad14..53efad4 100644
--- a/OpenMcdf/Fat.cs
+++ b/OpenMcdf/Fat.cs
@@ -57,7 +57,7 @@ void CacheCurrentSector()
 
         CfbBinaryReader reader = Context.Reader;
         reader.Position = current.Position;
-        reader.Read(cachedSectorBuffer);
+        reader.Read(cachedSectorBuffer, 0, cachedSectorBuffer.Length);
         cachedSector = current;
     }
 
diff --git a/OpenMcdf/MiniFat.cs b/OpenMcdf/MiniFat.cs
index 542f26e..c562de7 100644
--- a/OpenMcdf/MiniFat.cs
+++ b/OpenMcdf/MiniFat.cs
@@ -12,7 +12,7 @@ internal sealed class MiniFat : ContextBase, IEnumerable<FatEntry>, IDisposable
 {
     private readonly FatChainEnumerator fatChainEnumerator;
     private readonly int ElementsPerSector;
-    private readonly byte[] sector;
+    private readonly byte[] cachedSectorBuffer;
     private bool isDirty;
 
     public MiniFat(RootContextSite rootContextSite)
@@ -20,7 +20,7 @@ public MiniFat(RootContextSite rootContextSite)
     {
         ElementsPerSector = Context.SectorSize / sizeof(uint);
         fatChainEnumerator = new(Context.Fat, Context.Header.FirstMiniFatSectorId);
-        sector = new byte[Context.SectorSize];
+        cachedSectorBuffer = new byte[Context.SectorSize];
     }
 
     public void Dispose()
@@ -36,7 +36,7 @@ public void Flush()
         {
             CfbBinaryWriter writer = Context.Writer;
             writer.Position = fatChainEnumerator.CurrentSector.Position;
-            writer.Write(sector);
+            writer.Write(cachedSectorBuffer);
             isDirty = false;
         }
     }
@@ -74,7 +74,7 @@ bool TryMoveToSectorForKey(uint key, out long elementIndex)
 
         CfbBinaryReader reader = Context.Reader;
         reader.Position = fatChainEnumerator.CurrentSector.Position;
-        reader.Read(sector);
+        reader.Read(cachedSectorBuffer, 0, cachedSectorBuffer.Length);
         return true;
     }
 
@@ -88,7 +88,7 @@ public bool TryGetValue(uint key, out uint value)
             return false;
         }
 
-        Span<byte> slice = sector.AsSpan((int)elementIndex * sizeof(uint));
+        Span<byte> slice = cachedSectorBuffer.AsSpan((int)elementIndex * sizeof(uint));
         value = BinaryPrimitives.ReadUInt32LittleEndian(slice);
         return true;
     }
@@ -100,7 +100,7 @@ public bool TrySetValue(uint key, uint value)
         if (!TryMoveToSectorForKey(key, out long elementIndex))
             return false;
 
-        Span<byte> slice = sector.AsSpan((int)elementIndex * sizeof(uint));
+        Span<byte> slice = cachedSectorBuffer.AsSpan((int)elementIndex * sizeof(uint));
         BinaryPrimitives.WriteUInt32LittleEndian(slice, value);
         isDirty = true;
         return true;
diff --git a/OpenMcdf/StreamExtensions.cs b/OpenMcdf/StreamExtensions.cs
index e65b7e4..6bce7e3 100644
--- a/OpenMcdf/StreamExtensions.cs
+++ b/OpenMcdf/StreamExtensions.cs
@@ -11,20 +11,6 @@ internal static class StreamExtensions
 {
 #if !NET7_0_OR_GREATER
 
-    public static void ReadExactly(this Stream stream, Span<byte> buffer)
-    {
-        byte[] array = ArrayPool<byte>.Shared.Rent(buffer.Length);
-        try
-        {
-            stream.ReadExactly(array, 0, buffer.Length);
-            array.AsSpan(0, buffer.Length).CopyTo(buffer);
-        }
-        finally
-        {
-            ArrayPool<byte>.Shared.Return(array);
-        }
-    }
-
     public static void ReadExactly(this Stream stream, byte[] buffer, int offset, int count)
     {
         if (count == 0)
diff --git a/OpenMcdf/TransactedStream.cs b/OpenMcdf/TransactedStream.cs
index 29e948d..c32b509 100644
--- a/OpenMcdf/TransactedStream.cs
+++ b/OpenMcdf/TransactedStream.cs
@@ -104,7 +104,7 @@ public override void Write(byte[] buffer, int offset, int count)
         {
             // Copy the existing sector data
             originalStream.Position = originalPosition - sectorOffset;
-            originalStream.ReadExactly(this.buffer);
+            originalStream.ReadExactly(this.buffer, 0, this.buffer.Length);
 
             OverlayStream.Position = overlayPosition;
             OverlayStream.Write(this.buffer, 0, this.buffer.Length);
@@ -122,7 +122,7 @@ public void Commit()
         foreach (KeyValuePair<uint, long> entry in dirtySectorPositions)
         {
             OverlayStream.Position = entry.Value;
-            OverlayStream.ReadExactly(buffer);
+            OverlayStream.ReadExactly(buffer, 0, buffer.Length);
 
             originalStream.Position = entry.Key * Context.SectorSize;
             originalStream.Write(buffer, 0, buffer.Length);