diff --git a/fitparse/base.py b/fitparse/base.py
index b0ebf87..9967ba2 100644
--- a/fitparse/base.py
+++ b/fitparse/base.py
@@ -209,6 +209,8 @@ def _parse_file_header(self):
 
         # Larger fields are explicitly little endian from SDK
         header_size, protocol_ver_enc, profile_ver_enc, data_size = self._read_struct('2BHI4x', data=header_data)
+        if header_size < 12:
+            raise FitHeaderError('Irregular File Header Size')
 
         # Decode the same way the SDK does
         self.protocol_version = float("%d.%d" % (protocol_ver_enc >> 4, protocol_ver_enc & ((1 << 4) - 1)))
diff --git a/tests/test.py b/tests/test.py
index e4851d5..ec30be1 100755
--- a/tests/test.py
+++ b/tests/test.py
@@ -2,6 +2,7 @@
 
 import csv
 import datetime
+import io
 import os
 from struct import pack
 import warnings
@@ -74,6 +75,12 @@ def testfile(filename):
 
 
 class FitFileTestCase(unittest.TestCase):
+    def test_rejects_header_shorter_than_fit_minimum(self):
+        header = bytes([11, 16, 0, 0, 0, 0, 0, 0]) + b'.FIT'
+
+        with self.assertRaises(FitHeaderError):
+            FitFile(io.BytesIO(header), check_crc=False)
+
 
     def test_basic_file_with_one_record(self, endian='<'):
         f = FitFile(generate_fitfile(endian=endian))