diff --git a/SafeExamBrowser.Configuration.UnitTests/DataCompression/GZipCompressorTests.cs b/SafeExamBrowser.Configuration.UnitTests/DataCompression/GZipCompressorTests.cs
index 309e982d..f13d2a4d 100644
--- a/SafeExamBrowser.Configuration.UnitTests/DataCompression/GZipCompressorTests.cs
+++ b/SafeExamBrowser.Configuration.UnitTests/DataCompression/GZipCompressorTests.cs
@@ -83,6 +83,16 @@ namespace SafeExamBrowser.Configuration.UnitTests.DataCompression
 
 			var preview = sut.Peek(compressed, 5);
 
+			try
+			{
+				var position = compressed.Position;
+				var length = compressed.Length;
+			}
+			catch (ObjectDisposedException)
+			{
+				Assert.Fail("Source stream was disposed after previewing data!");
+			}
+
 			Assert.AreEqual(5, preview.Length);
 			Assert.IsTrue(Encoding.UTF8.GetBytes("A com").SequenceEqual(preview));
 		}
diff --git a/SafeExamBrowser.Configuration/DataCompression/GZipCompressor.cs b/SafeExamBrowser.Configuration/DataCompression/GZipCompressor.cs
index 3c8aac99..2d639feb 100644
--- a/SafeExamBrowser.Configuration/DataCompression/GZipCompressor.cs
+++ b/SafeExamBrowser.Configuration/DataCompression/GZipCompressor.cs
@@ -103,10 +103,9 @@ namespace SafeExamBrowser.Configuration.DataCompression
 
 		public byte[] Peek(Stream data, int count)
 		{
-			var stream = new GZipStream(data, CompressionMode.Decompress);
-
 			data.Seek(0, SeekOrigin.Begin);
 
+			using (var stream = new GZipStream(data, CompressionMode.Decompress, true))
 			using (var decompressed = new MemoryStream())
 			{
 				var buffer = new byte[count];