diff --git a/OpenRA.Game/FileFormats/VqaReader.cs b/OpenRA.Game/FileFormats/VqaReader.cs
index 32fc066b63..ab7f9cb218 100644
--- a/OpenRA.Game/FileFormats/VqaReader.cs
+++ b/OpenRA.Game/FileFormats/VqaReader.cs
@@ -315,7 +315,7 @@ namespace OpenRA.FileFormats
 					// Full frame-modifier
 					case "CBFZ":
 						var decodeMode = s.Peek() == 0;
-						s.Read(fileBuffer, 0, subchunkLength);
+						s.ReadBytes(fileBuffer, 0, subchunkLength);
 						Array.Clear(cbf, 0, cbf.Length);
 						Array.Clear(cbfBuffer, 0, cbfBuffer.Length);
 						var decodeCount = 0;
@@ -386,7 +386,7 @@ namespace OpenRA.FileFormats
 						return;
 					case "VPRZ":
 						Array.Clear(origData, 0, origData.Length);
-						s.Read(fileBuffer, 0, subchunkLength);
+						s.ReadBytes(fileBuffer, 0, subchunkLength);
 						if (fileBuffer[0] != 0)
 							vtprSize = Format80.DecodeInto(fileBuffer, origData);
 						else
@@ -394,7 +394,7 @@ namespace OpenRA.FileFormats
 						return;
 					case "VPTR":
 						Array.Clear(origData, 0, origData.Length);
-						s.Read(origData, 0, subchunkLength);
+						s.ReadBytes(origData, 0, subchunkLength);
 						vtprSize = subchunkLength;
 						return;
 					default:
diff --git a/OpenRA.Game/StreamExts.cs b/OpenRA.Game/StreamExts.cs
index b525e67ed9..eb9699cc77 100755
--- a/OpenRA.Game/StreamExts.cs
+++ b/OpenRA.Game/StreamExts.cs
@@ -28,6 +28,8 @@ namespace OpenRA
 
 		public static void ReadBytes(this Stream s, byte[] buffer, int offset, int count)
 		{
+			if (count < 0)
+				throw new ArgumentOutOfRangeException("count", "Non-negative number required.");
 			while (count > 0)
 			{
 				int bytesRead;