diff --git a/Lib/test/test_tarfile.py b/Lib/test/test_tarfile.py
index 2db18fe..c0741ee 100644
--- a/Lib/test/test_tarfile.py
+++ b/Lib/test/test_tarfile.py
@@ -1126,11 +1126,32 @@
 
     format = tarfile.GNU_FORMAT
 
+    def test_bad_pax_header(self):
+        # Test for issue #8633. GNU tar <= 1.23 creates raw binary fields
+        # without a hdrcharset=BINARY header.
+        for encoding, name in (("utf8", "pax/bad-pax-\udce4\udcf6\udcfc"),
+                ("iso8859-1", "pax/bad-pax-\xe4\xf6\xfc"),):
+            with tarfile.open(tarname, encoding=encoding, errors="surrogateescape") as tar:
+                try:
+                    t = tar.getmember(name)
+                except KeyError:
+                    self.fail("unable to read bad GNU tar pax header")
+
 
 class PAXUnicodeTest(UstarUnicodeTest):
 
     format = tarfile.PAX_FORMAT
 
+    def test_binary_header(self):
+        # Test a POSIX.1-2008 compatible header with a hdrcharset=BINARY field.
+        for encoding, name in (("utf8", "pax/hdrcharset-\udce4\udcf6\udcfc"),
+                ("iso8859-1", "pax/hdrcharset-\xe4\xf6\xfc"),):
+            with tarfile.open(tarname, encoding=encoding, errors="surrogateescape") as tar:
+                try:
+                    t = tar.getmember(name)
+                except KeyError:
+                    self.fail("unable to read POSIX.1-2008 binary header")
+
 
 class AppendTest(unittest.TestCase):
     # Test append mode (cp. patch #1652681).
diff --git a/Lib/test/testtar.tar b/Lib/test/testtar.tar
index b5bb46b..c3022ed 100644
--- a/Lib/test/testtar.tar
+++ b/Lib/test/testtar.tar
Binary files differ