diff --git a/tools/binctl b/tools/binctl
index 49ddff478..1aa71acb9 100755
--- a/tools/binctl
+++ b/tools/binctl
@@ -54,9 +54,6 @@ class BinImage(object):
         assert self.reserved2 == 415 * b'\x00'
         self.code = data[self.hdrlen:]
         assert len(self.code) == self.codelen
-        h = pyblake2.blake2s(data[:IMAGE_HEADER_SIZE - 65])
-        h.update(b'\x00' * 65)
-        self.fingerprint = h.hexdigest()
 
     def print(self):
         if self.magic == b'TRZF':
@@ -79,7 +76,7 @@ class BinImage(object):
         print('  * sigmask :', format_sigmask(self.sigmask))
         print('  * sig     :', binascii.hexlify(self.sig).decode())
         print('  * total   : %d bytes' % total_len)
-        print('  * fngprnt :', self.fingerprint)
+        print('  * fngprnt :', self.fingerprint())
         print()
 
     def compute_hashes(self):
@@ -120,6 +117,9 @@ class BinImage(object):
         assert len(header) == self.hdrlen
         return header
 
+    def fingerprint(self):
+        return pyblake2.blake2s(self.serialize_header(False)).hexdigest()
+
     def sign(self, sigmask, signature):
         header = self.serialize_header(sig=False)
         data = header + self.code