diff --git a/client/openapi/trustd.yaml b/client/openapi/trustd.yaml
index bee4cbb61..97198b9e7 100644
--- a/client/openapi/trustd.yaml
+++ b/client/openapi/trustd.yaml
@@ -2150,28 +2150,29 @@ components:
       allOf:
       - $ref: '#/components/schemas/VulnerabilityHead'
       - type: object
-        required:
-        - severity
-        - score
         properties:
           score:
-            type: number
+            type:
+            - number
+            - 'null'
             format: double
             description: |-
               The average (arithmetic mean) score this advisory assigns to
               the particular vulnerability.
           severity:
-            $ref: '#/components/schemas/Severity'
-            description: |-
-              The English-language word description of the severity of the given
-              vulnerability, as asserted by the advisory, using the CVSS bucketing
-              ranges.
+            oneOf:
+            - type: 'null'
+            - $ref: '#/components/schemas/Severity'
+              description: |-
+                The English-language word description of the severity of the given
+                vulnerability, as asserted by the advisory, using the CVSS bucketing
+                ranges.
 
-              Critical: 9.0–10.0
-              High: 7.0–8.9
-              Medium: 4.0–6.9
-              Low: 0.1–3.9
-              None: 0
+                Critical: 9.0–10.0
+                High: 7.0–8.9
+                Medium: 4.0–6.9
+                Low: 0.1–3.9
+                None: 0
     AdvisoryVulnerabilitySummary:
       allOf:
       - $ref: '#/components/schemas/AdvisoryVulnerabilityHead'