diff --git a/odoo/tools/mimetypes.py b/odoo/tools/mimetypes.py
index 017b34faf11..3c30b3ace83 100644
--- a/odoo/tools/mimetypes.py
+++ b/odoo/tools/mimetypes.py
@@ -5,6 +5,7 @@ Mimetypes-related utilities
 # TODO: reexport stdlib mimetypes?
 """
 import collections
+import functools
 import io
 import logging
 import re
@@ -133,7 +134,7 @@ _mime_mappings = (
     # zip, but will include jar, odt, ods, odp, docx, xlsx, pptx, apk
     _Entry('application/zip', [b'PK\x03\x04'], [_check_ooxml, _check_open_container_format]),
 )
-def guess_mimetype(bin_data, default='application/octet-stream'):
+def _odoo_guess_mimetype(bin_data, default='application/octet-stream'):
     """ Attempts to guess the mime type of the provided binary data, similar
     to but significantly more limited than libmagic
 
@@ -166,17 +167,28 @@ try:
     import magic
 except ImportError:
     magic = None
-else:
-    # There are 2 python libs named 'magic' with incompatible api.
 
+if magic:
+    # There are 2 python libs named 'magic' with incompatible api.
     # magic from pypi https://pypi.python.org/pypi/python-magic/
-    if hasattr(magic,'from_buffer'):
-        guess_mimetype = lambda bin_data, default=None: magic.from_buffer(bin_data, mime=True)
+    if hasattr(magic, 'from_buffer'):
+        _guesser = functools.partial(magic.from_buffer, mime=True)
     # magic from file(1) https://packages.debian.org/squeeze/python-magic
-    elif hasattr(magic,'open'):
+    elif hasattr(magic, 'open'):
         ms = magic.open(magic.MAGIC_MIME_TYPE)
         ms.load()
-        guess_mimetype = lambda bin_data, default=None: ms.buffer(bin_data)
+        _guesser = ms.buffer
+
+    def guess_mimetype(bin_data, default=None):
+        mimetype = _guesser(bin_data)
+        # upgrade incorrect mimetype to official one, fixed upstream
+        # https://github.com/file/file/commit/1a08bb5c235700ba623ffa6f3c95938fe295b262
+        if mimetype == 'image/svg':
+            return 'image/svg+xml'
+        return mimetype
+else:
+    guess_mimetype = _odoo_guess_mimetype
+
 
 def neuter_mimetype(mimetype, user):
     wrong_type = 'ht' in mimetype or 'xml' in mimetype or 'svg' in mimetype