diff --git a/vulnerabilities/importer.py b/vulnerabilities/importer.py
index 005534512..682901e83 100644
--- a/vulnerabilities/importer.py
+++ b/vulnerabilities/importer.py
@@ -223,18 +223,30 @@ def from_dict(cls, affected_pkg: dict):
         """
         package = PackageURL(**affected_pkg["package"])
         affected_version_range = None
-        if (
-            affected_pkg["affected_version_range"]
-            and affected_pkg["affected_version_range"] != "None"
-        ):
-            affected_version_range = VersionRange.from_string(
-                affected_pkg["affected_version_range"]
-            )
+        affected_range = affected_pkg["affected_version_range"]
+
+        # TODO: "None" is a likely bug
+        if affected_range and affected_range != "None":
+            try:
+                affected_version_range = VersionRange.from_string(affected_range)
+            except:
+                tb = traceback.format_exc()
+                logger.error(
+                    f"Cannot create AffectedPackage with invalid or unknown range: {affected_pkg!r} with error: {tb!r}"
+                )
+                return
+
         fixed_version = affected_pkg["fixed_version"]
         if fixed_version and affected_version_range:
             # TODO: revisit after https://github.com/nexB/univers/issues/10
             fixed_version = affected_version_range.version_class(fixed_version)
 
+        if not fixed_version and not affected_version_range:
+            logger.error(
+                f"Cannot create AffectedPackage without fixed version or affected range: {affected_pkg!r}"
+            )
+            return
+
         return cls(
             package=package,
             affected_version_range=affected_version_range,
@@ -295,7 +307,9 @@ def from_dict(cls, advisory_data):
             "aliases": advisory_data["aliases"],
             "summary": advisory_data["summary"],
             "affected_packages": [
-                AffectedPackage.from_dict(pkg) for pkg in advisory_data["affected_packages"]
+                AffectedPackage.from_dict(pkg)
+                for pkg in advisory_data["affected_packages"]
+                if pkg is not None
             ],
             "references": [Reference.from_dict(ref) for ref in advisory_data["references"]],
             "date_published": datetime.datetime.fromisoformat(date_published)
diff --git a/vulnerabilities/improvers/default.py b/vulnerabilities/improvers/default.py
index 720a143e8..a2e49e9f2 100644
--- a/vulnerabilities/improvers/default.py
+++ b/vulnerabilities/improvers/default.py
@@ -105,6 +105,8 @@ def get_exact_purls(affected_package: AffectedPackage) -> Tuple[List[PackageURL]
     ... )
     >>> assert expected == got
     """
+    if not affected_package:
+        return [], []
 
     try:
         vr = affected_package.affected_version_range
diff --git a/vulnerabilities/models.py b/vulnerabilities/models.py
index fc5eb5e3c..903443fa1 100644
--- a/vulnerabilities/models.py
+++ b/vulnerabilities/models.py
@@ -1137,7 +1137,9 @@ def to_advisory_data(self) -> "AdvisoryData":
         return AdvisoryData(
             aliases=self.aliases,
             summary=self.summary,
-            affected_packages=[AffectedPackage.from_dict(pkg) for pkg in self.affected_packages],
+            affected_packages=[
+                AffectedPackage.from_dict(pkg) for pkg in self.affected_packages if pkg
+            ],
             references=[Reference.from_dict(ref) for ref in self.references],
             date_published=self.date_published,
             weaknesses=self.weaknesses,
diff --git a/vulnerabilities/tests/test_default_improver.py b/vulnerabilities/tests/test_default_improver.py
index 703e985a4..005a2d12c 100644
--- a/vulnerabilities/tests/test_default_improver.py
+++ b/vulnerabilities/tests/test_default_improver.py
@@ -17,6 +17,7 @@
 from vulnerabilities.importer import Reference
 from vulnerabilities.improver import Inference
 from vulnerabilities.improvers.default import DefaultImprover
+from vulnerabilities.improvers.default import get_exact_purls
 from vulnerabilities.tests import util_tests
 
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
@@ -136,3 +137,29 @@ def test_default_improver_with_nvd():
         for data in list(default_improver.get_inferences(AdvisoryData.from_dict(advisory_data)))
     ]
     util_tests.check_results_against_json(result, expected_file)
+
+
+def test_AffectedPackage_from_dict_should_not_crash_with_invalid_version_range():
+    package = PackageURL(
+        type="rpm",
+        namespace="rpms",
+        name="python",
+        qualifiers={},
+        subpath=None,
+    )
+
+    test_ranges = [
+        # foo is a non-existing range
+        "vers:foo/1.2.3",
+        # apache was not supported and returned from vulnerabilities.importers.apache_httpd.ApacheHTTPDImporter
+        "vers:apache/",
+        None,
+    ]
+    for tr in test_ranges:
+        pkg = {
+            "package": package.to_dict(),
+            "affected_version_range": tr,
+            "fixed_version": None,
+        }
+
+        assert AffectedPackage.from_dict(pkg) is None