diff --git a/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/ClassNames.java b/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/ClassNames.java
index 3f79f8d71ba34..f7e6bd6d5f620 100644
--- a/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/ClassNames.java
+++ b/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/ClassNames.java
@@ -455,6 +455,9 @@ private static DotName createConstant(String fqcn) {
             createConstant("java.util.UUID"),
             createConstant("java.lang.Void"));
 
+    public static final List<DotName> STANDARD_STACK_ELEMENT_TYPES = List.of(
+            createConstant("org.hibernate.query.sqm.tree.select.SqmQueryPart"));
+
     public static final DotName HIBERNATE_ORM_PROCESSOR = createConstant(
             "io.quarkus.hibernate.orm.deployment.HibernateOrmProcessor");
 
diff --git a/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/GraalVMFeatures.java b/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/GraalVMFeatures.java
index 652de267cc10f..d964cdae8694c 100644
--- a/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/GraalVMFeatures.java
+++ b/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/GraalVMFeatures.java
@@ -39,4 +39,14 @@ ReflectiveClassBuildItem registerJdbcArrayTypesForReflection() {
                 .build();
     }
 
+    // Workaround for https://hibernate.atlassian.net/browse/HHH-18875
+    // See https://hibernate.zulipchat.com/#narrow/channel/132094-hibernate-orm-dev/topic/StandardStack.20and.20reflection
+    @BuildStep
+    ReflectiveClassBuildItem registerStandardStackElementTypesForReflection() {
+        return ReflectiveClassBuildItem
+                .builder(ClassNames.STANDARD_STACK_ELEMENT_TYPES.stream().map(d -> d.toString() + "[]").toArray(String[]::new))
+                .reason("Workaround for https://hibernate.atlassian.net/browse/HHH-18875")
+                .build();
+    }
+
 }
diff --git a/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/integration/QuarkusEnhancementContext.java b/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/integration/QuarkusEnhancementContext.java
index bdbbe3ee916b3..4a42c87dac784 100644
--- a/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/integration/QuarkusEnhancementContext.java
+++ b/extensions/hibernate-orm/deployment/src/main/java/io/quarkus/hibernate/orm/deployment/integration/QuarkusEnhancementContext.java
@@ -2,6 +2,7 @@
 
 import org.hibernate.bytecode.enhance.spi.DefaultEnhancementContext;
 import org.hibernate.bytecode.enhance.spi.UnloadedField;
+import org.hibernate.bytecode.enhance.spi.UnsupportedEnhancementStrategy;
 
 public final class QuarkusEnhancementContext extends DefaultEnhancementContext {
 
@@ -26,4 +27,17 @@ public ClassLoader getLoadingClassLoader() {
         throw new IllegalStateException("The Classloader of the EnhancementContext should not be used");
     }
 
+    @Override
+    public UnsupportedEnhancementStrategy getUnsupportedEnhancementStrategy() {
+        // We expect model classes to be enhanced.
+        // Lack of enhancement could lead to many problems,
+        // from bad performance, to Quarkus-specific optimizations causing errors/data loss,
+        // to incorrect generated bytecode (references to non-existing methods).
+        // For backwards compatibility reason, in this branch we adopt the legacy behavior of Hibernate ORM,
+        // which is to try to enhance all classes, ignoring any known issue.
+        // However, later versions of Quarkus (3.17+ at least) just have Hibernate ORM's enhancer fail.
+        // with a clear error message pointing to the application class that needs to be fixed.
+        return UnsupportedEnhancementStrategy.LEGACY;
+    }
+
 }
diff --git a/extensions/hibernate-orm/deployment/src/test/java/io/quarkus/hibernate/orm/deployment/ClassNamesTest.java b/extensions/hibernate-orm/deployment/src/test/java/io/quarkus/hibernate/orm/deployment/ClassNamesTest.java
index 60b94f4c7ddef..66ca64943ca52 100644
--- a/extensions/hibernate-orm/deployment/src/test/java/io/quarkus/hibernate/orm/deployment/ClassNamesTest.java
+++ b/extensions/hibernate-orm/deployment/src/test/java/io/quarkus/hibernate/orm/deployment/ClassNamesTest.java
@@ -107,6 +107,8 @@ public void testNoMissingHibernateAnnotation() {
     }
 
     private static void ignoreInternalAnnotations(Set<DotName> annotationSet) {
+        annotationSet.removeIf(name -> name.toString().equals("org.hibernate.cfg.Compatibility"));
+        annotationSet.removeIf(name -> name.toString().equals("org.hibernate.cfg.Unsafe"));
         annotationSet.removeIf(name -> name.toString().equals("org.hibernate.Incubating"));
         annotationSet.removeIf(name -> name.toString().equals("org.hibernate.Internal"));
         annotationSet.removeIf(name -> name.toString().equals("org.hibernate.Remove"));
diff --git a/pom.xml b/pom.xml
index bbdcf6d9e96ab..f24d3a25d994b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -71,7 +71,7 @@
         <jacoco.version>0.8.12</jacoco.version>
         <kubernetes-client.version>6.13.4</kubernetes-client.version> <!-- Please check with Java Operator SDK team before updating -->
         <rest-assured.version>5.5.0</rest-assured.version>
-        <hibernate-orm.version>6.6.1.Final</hibernate-orm.version> <!-- WARNING when updating, also align the versions below -->
+        <hibernate-orm.version>6.6.3.Final</hibernate-orm.version> <!-- WARNING when updating, also align the versions below -->
         <antlr.version>4.13.0</antlr.version> <!-- version controlled by Hibernate ORM's needs -->
         <bytebuddy.version>1.14.18</bytebuddy.version> <!-- version controlled by Hibernate ORM's needs -->
         <hibernate-commons-annotations.version>7.0.3.Final</hibernate-commons-annotations.version> <!-- version controlled by Hibernate ORM's needs -->