diff --git a/swh/indexer/metadata_dictionary/cff.py b/swh/indexer/metadata_dictionary/cff.py
--- a/swh/indexer/metadata_dictionary/cff.py
+++ b/swh/indexer/metadata_dictionary/cff.py
@@ -22,14 +22,19 @@
     mapping = CROSSWALK_TABLE["Citation File Format Core (CFF-Core) 1.0.2"]
     string_fields = ["keywords", "license", "abstract", "version", "doi"]
 
-    def translate(self, raw_content: bytes) -> Dict[str, str]:
+    def translate(self, raw_content: bytes) -> Optional[Dict[str, str]]:
         raw_content_string: str = raw_content.decode()
-        content_dict = yaml.load(raw_content_string, Loader=SafeLoader)
-        metadata = self._translate_dict(content_dict)
+        try:
+            content_dict = yaml.load(raw_content_string, Loader=SafeLoader)
+        except yaml.scanner.ScannerError:
+            return None
 
-        metadata["@context"] = CODEMETA_CONTEXT_URL
+        if isinstance(content_dict, dict):
+            metadata = self._translate_dict(content_dict)
+            metadata["@context"] = CODEMETA_CONTEXT_URL
+            return metadata
 
-        return metadata
+        return None
 
     def normalize_authors(self, d: List[dict]) -> Dict[str, list]:
         result = []
diff --git a/swh/indexer/tests/test_metadata.py b/swh/indexer/tests/test_metadata.py
--- a/swh/indexer/tests/test_metadata.py
+++ b/swh/indexer/tests/test_metadata.py
@@ -159,6 +159,59 @@
         # then
         assert expected == result
 
+    def test_compute_metadata_cff_invalid_yaml(self):
+        """
+        test yaml translation for invalid yaml file
+        """
+        # given
+        content = """cff-version: 1.0.3
+message: To cite the SigMF specification, please include the following:
+authors:
+  - name: The GNU Radio Foundation, Inc.
+        """.encode(
+            "utf-8"
+        )
+
+        expected = None
+
+        result = self.cff_mapping.translate(content)
+        # then
+        assert expected == result
+
+    def test_compute_metadata_cff_empty(self):
+        """
+        test yaml translation for empty yaml file
+        """
+        # given
+        content = """
+        """.encode(
+            "utf-8"
+        )
+
+        expected = None
+
+        result = self.cff_mapping.translate(content)
+        # then
+        assert expected == result
+
+    def test_compute_metadata_cff_list(self):
+        """
+        test yaml translation for empty yaml file
+        """
+        # given
+        content = """
+- Foo
+- Bar
+        """.encode(
+            "utf-8"
+        )
+
+        expected = None
+
+        result = self.cff_mapping.translate(content)
+        # then
+        assert expected == result
+
     def test_compute_metadata_npm(self):
         """
         testing only computation of metadata with hard_mapping_npm