diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index fce90ef9..68e315c6 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<files psalm-version="4.18.1@dda05fa913f4dc6eb3386f2f7ce5a45d37a71bcb">
+<files psalm-version="4.19.0@a2ad69ae4f5ab1f7d225a8dc4e2ec2d9415ed599">
   <file src="src/CallableNormalizer.php">
     <MixedInferredReturnType occurrences="1">
       <code>Json</code>
@@ -21,13 +21,12 @@
     <MissingParamType occurrences="1">
       <code>$data</code>
     </MissingParamType>
-    <MixedArgument occurrences="8">
+    <MixedArgument occurrences="7">
       <code>$anyOfSchema</code>
       <code>$item</code>
       <code>$item</code>
       <code>$itemSchema</code>
       <code>$oneOfSchema</code>
-      <code>$schema-&gt;properties</code>
       <code>$value</code>
       <code>$value</code>
     </MixedArgument>
diff --git a/src/SchemaNormalizer.php b/src/SchemaNormalizer.php
index dbf22a24..fef7da24 100644
--- a/src/SchemaNormalizer.php
+++ b/src/SchemaNormalizer.php
@@ -177,7 +177,10 @@ private function normalizeObject(
         /**
          * @see https://json-schema.org/understanding-json-schema/reference/object.html#properties
          */
-        if (\property_exists($schema, 'properties')) {
+        if (
+            \property_exists($schema, 'properties')
+            && \is_object($schema->properties)
+        ) {
             /** @var array<string, \stdClass> $objectPropertiesThatAreDefinedBySchema */
             $objectPropertiesThatAreDefinedBySchema = \array_intersect_key(
                 \get_object_vars($schema->properties),