diff --git a/vulnerabilities/importer.py b/vulnerabilities/importer.py
index aaac910a1..698b2f251 100644
--- a/vulnerabilities/importer.py
+++ b/vulnerabilities/importer.py
@@ -233,7 +233,7 @@ class AdvisoryData:
     """
 
     aliases: List[str] = dataclasses.field(default_factory=list)
-    summary: Optional[str] = None
+    summary: Optional[str] = ""
     affected_packages: List[AffectedPackage] = dataclasses.field(default_factory=list)
     references: List[Reference] = dataclasses.field(default_factory=list)
     date_published: Optional[datetime.datetime] = None
diff --git a/vulnerabilities/improver.py b/vulnerabilities/improver.py
index f0ec5cd9d..54a0a9b18 100644
--- a/vulnerabilities/improver.py
+++ b/vulnerabilities/improver.py
@@ -29,7 +29,7 @@ class Inference:
     vulnerability_id: str = None
     aliases: Optional[List[str]] = dataclasses.field(default_factory=list)
     confidence: int = MAX_CONFIDENCE
-    summary: Optional[str] = None
+    summary: Optional[str] = ""
     affected_purls: Optional[List[PackageURL]] = dataclasses.field(default_factory=list)
     fixed_purl: PackageURL = None
     references: List[Reference] = dataclasses.field(default_factory=list)
diff --git a/vulnerabilities/migrations/0009_alter_advisory_summary_and_more.py b/vulnerabilities/migrations/0009_alter_advisory_summary_and_more.py
new file mode 100644
index 000000000..3b8ce5f90
--- /dev/null
+++ b/vulnerabilities/migrations/0009_alter_advisory_summary_and_more.py
@@ -0,0 +1,33 @@
+# Generated by Django 4.0.3 on 2022-04-15 18:39
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('vulnerabilities', '0008_alter_vulnerabilityseverity_scoring_system'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='advisory',
+            name='summary',
+            field=models.TextField(blank=True),
+        ),
+        migrations.AlterField(
+            model_name='advisory',
+            name='unique_content_id',
+            field=models.CharField(blank=True, max_length=32),
+        ),
+        migrations.AlterField(
+            model_name='vulnerability',
+            name='summary',
+            field=models.TextField(blank=True, help_text='Summary of the vulnerability'),
+        ),
+        migrations.AlterField(
+            model_name='vulnerabilityreference',
+            name='reference_id',
+            field=models.CharField(blank=True, help_text='An optional reference ID, such as DSA-4465-1 when available', max_length=200),
+        ),
+    ]
diff --git a/vulnerabilities/models.py b/vulnerabilities/models.py
index ebc9bf141..dee7773aa 100644
--- a/vulnerabilities/models.py
+++ b/vulnerabilities/models.py
@@ -57,7 +57,6 @@ class Vulnerability(models.Model):
 
     summary = models.TextField(
         help_text="Summary of the vulnerability",
-        null=True,
         blank=True,
     )
 
@@ -104,7 +103,6 @@ class VulnerabilityReference(models.Model):
         max_length=200,
         help_text="An optional reference ID, such as DSA-4465-1 when available",
         blank=True,
-        null=True,
     )
 
     @property
@@ -324,9 +322,14 @@ class Advisory(models.Model):
     into structured data
     """
 
-    unique_content_id = models.CharField(max_length=32, blank=True, null=True)
+    unique_content_id = models.CharField(
+        max_length=32,
+        blank=True,
+    )
     aliases = models.JSONField(blank=True, default=list, help_text="A list of alias strings")
-    summary = models.TextField(blank=True, null=True)
+    summary = models.TextField(
+        blank=True,
+    )
     # we use a JSON field here to avoid creating a complete relational model for data that
     # is never queried directly; instead it is only retrieved and processed as a whole by
     # an improver
diff --git a/vulnerabilities/tests/test_alpine.py b/vulnerabilities/tests/test_alpine.py
index 3f1f5f950..26538f4cf 100644
--- a/vulnerabilities/tests/test_alpine.py
+++ b/vulnerabilities/tests/test_alpine.py
@@ -43,7 +43,7 @@ def test_process_record(caplog):
     expected_advisories = [
         AdvisoryData(
             aliases=[],
-            summary=None,
+            summary="",
             affected_packages=[
                 AffectedPackage(
                     package=PackageURL(
@@ -149,7 +149,7 @@ def test_process_record(caplog):
         ),
         AdvisoryData(
             aliases=["CVE-2018-7540"],
-            summary=None,
+            summary="",
             affected_packages=[
                 AffectedPackage(
                     package=PackageURL(
@@ -255,7 +255,7 @@ def test_process_record(caplog):
         ),
         AdvisoryData(
             aliases=["CVE-2017-9669"],
-            summary=None,
+            summary="",
             affected_packages=[
                 AffectedPackage(
                     package=PackageURL(
@@ -355,7 +355,7 @@ def test_process_record(caplog):
         ),
         AdvisoryData(
             aliases=["CVE-2017-9671"],
-            summary=None,
+            summary="",
             affected_packages=[
                 AffectedPackage(
                     package=PackageURL(