diff --git a/swh/web/ui/converters.py b/swh/web/ui/converters.py
--- a/swh/web/ui/converters.py
+++ b/swh/web/ui/converters.py
@@ -159,16 +159,31 @@
         - sha1s are in hexadecimal strings (id, directory)
         - bytes are decoded in string (author_name, committer_name,
         author_email, committer_email, message)
+        - if message is not utf-8 encoded, message is null and msg_url points
+        to the api endpoint to download the revision message as is
         - remaining keys are left as is
 
     """
-    return from_swh(revision,
-                    hashess=set(['id', 'directory', 'parents', 'children']),
-                    bytess=set(['name',
-                                'fullname',
-                                'email',
-                                'message']),
-                    dates={'date', 'committer_date'})
+    revision = from_swh(revision,
+                        hashess=set(['id',
+                                     'directory',
+                                     'parents',
+                                     'children']),
+                        bytess=set(['name',
+                                    'fullname',
+                                    'email']),
+                        dates={'date', 'committer_date'})
+
+    if revision:
+        if 'message' in revision:
+            try:
+                revision['message'] = revision['message'].decode('utf-8')
+            except UnicodeDecodeError:
+                revision['message'] = None
+                revision['msg_url'] = ('/api/1/revision/''%s/raw/'
+                                       % revision['id'])
+
+    return revision
 
 
 def from_content(content):
diff --git a/swh/web/ui/tests/test_converters.py b/swh/web/ui/tests/test_converters.py
--- a/swh/web/ui/tests/test_converters.py
+++ b/swh/web/ui/tests/test_converters.py
@@ -326,6 +326,108 @@
         self.assertEqual(actual_revision, expected_revision)
 
     @istest
+    def from_revision_invalid(self):
+        revision_input = {
+            'id': hashutil.hex_to_hash(
+                '18d8be353ed3480476f032475e7c233eff7371d5'),
+            'directory': hashutil.hex_to_hash(
+                '7834ef7e7c357ce2af928115c6c6a42b7e2a44e6'),
+            'author': {
+                'name': b'Software Heritage',
+                'fullname': b'robot robot@softwareheritage.org',
+                'email': b'robot@softwareheritage.org',
+            },
+            'committer': {
+                'name': b'Software Heritage',
+                'fullname': b'robot robot@softwareheritage.org',
+                'email': b'robot@softwareheritage.org',
+            },
+            'message': b'invalid message \xff',
+            'date': {
+                'timestamp': datetime.datetime(
+                    2000, 1, 17, 11, 23, 54,
+                    tzinfo=datetime.timezone.utc).timestamp(),
+                'offset': 0,
+                'negative_utc': False,
+            },
+            'committer_date': {
+                'timestamp': datetime.datetime(
+                    2000, 1, 17, 11, 23, 54,
+                    tzinfo=datetime.timezone.utc).timestamp(),
+                'offset': 0,
+                'negative_utc': False,
+            },
+            'synthetic': True,
+            'type': 'tar',
+            'parents': [
+                hashutil.hex_to_hash(
+                    '29d8be353ed3480476f032475e7c244eff7371d5'),
+                hashutil.hex_to_hash(
+                    '30d8be353ed3480476f032475e7c244eff7371d5')
+            ],
+            'children': [
+                hashutil.hex_to_hash(
+                    '123546353ed3480476f032475e7c244eff7371d5'),
+            ],
+            'metadata': {
+                'original_artifact': [{
+                    'archive_type': 'tar',
+                    'name': 'webbase-5.7.0.tar.gz',
+                    'sha1': '147f73f369733d088b7a6fa9c4e0273dcd3c7ccd',
+                    'sha1_git': '6a15ea8b881069adedf11feceec35588f2cfe8f1',
+                    'sha256': '401d0df797110bea805d358b85bcc1ced29549d3d73f'
+                    '309d36484e7edf7bb912',
+
+                }]
+            },
+        }
+
+        expected_revision = {
+            'id': '18d8be353ed3480476f032475e7c233eff7371d5',
+            'directory': '7834ef7e7c357ce2af928115c6c6a42b7e2a44e6',
+            'author': {
+                'name': 'Software Heritage',
+                'fullname': 'robot robot@softwareheritage.org',
+                'email': 'robot@softwareheritage.org',
+            },
+            'committer': {
+                'name': 'Software Heritage',
+                'fullname': 'robot robot@softwareheritage.org',
+                'email': 'robot@softwareheritage.org',
+            },
+            'message': None,
+            'msg_url': '/api/1/revision/'
+            '18d8be353ed3480476f032475e7c233eff7371d5/raw/',
+            'date': "2000-01-17T11:23:54+00:00",
+            'committer_date': "2000-01-17T11:23:54+00:00",
+            'children': [
+                '123546353ed3480476f032475e7c244eff7371d5'
+            ],
+            'parents': [
+                '29d8be353ed3480476f032475e7c244eff7371d5',
+                '30d8be353ed3480476f032475e7c244eff7371d5'
+            ],
+            'type': 'tar',
+            'synthetic': True,
+            'metadata': {
+                'original_artifact': [{
+                    'archive_type': 'tar',
+                    'name': 'webbase-5.7.0.tar.gz',
+                    'sha1': '147f73f369733d088b7a6fa9c4e0273dcd3c7ccd',
+                    'sha1_git': '6a15ea8b881069adedf11feceec35588f2cfe8f1',
+                    'sha256': '401d0df797110bea805d358b85bcc1ced29549d3d73f'
+                    '309d36484e7edf7bb912'
+                }]
+            },
+        }
+
+        # when
+        actual_revision = converters.from_revision(revision_input)
+
+        # then
+        self.assertEqual(actual_revision, expected_revision)
+
+    @istest
     def from_content(self):
         content_input = {
             'sha1': hashutil.hex_to_hash('5c6f0e2750f48fa0bd0c4cf5976ba0b9e0'