diff --git a/src/NerdBank.GitVersioning/ManagedGit/ZLibStream.cs b/src/NerdBank.GitVersioning/ManagedGit/ZLibStream.cs
index 31d11366..d21077f5 100644
--- a/src/NerdBank.GitVersioning/ManagedGit/ZLibStream.cs
+++ b/src/NerdBank.GitVersioning/ManagedGit/ZLibStream.cs
@@ -5,6 +5,7 @@
 using System.Buffers;
 using System.IO;
 using System.IO.Compression;
+using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -56,9 +57,9 @@ public ZLibStream(Stream stream, long length = -1)
             Span<byte> zlibHeader = stackalloc byte[2];
             stream.ReadAll(zlibHeader);
 
-            if (zlibHeader[0] != 0x78 || (zlibHeader[1] != 0x01 && zlibHeader[1] != 0x9C))
+            if (zlibHeader[0] != 0x78 || (zlibHeader[1] != 0x01 && zlibHeader[1] != 0x9C && zlibHeader[1] != 0x5E && zlibHeader[1] != 0xDA))
             {
-                throw new GitException();
+                throw new GitException($"Invalid zlib header {string.Join(" ", zlibHeader.ToArray().Select(b => $"{b:X2}"))}");
             }
         }