CAMEL-24294: enforce the typeFilters allow-list in the SnakeYAML TagInspector

components/camel-snakeyaml/src/main/java/org/apache/camel/component/snakeyaml/SnakeYAMLDataFormat.java

@@ -332,7 +332,9 @@ protected Class<?> getClassForName(String name) throws ClassNotFoundException {
     final class TrustedTagInspector implements TagInspector {
         @Override
         public boolean isGlobalTagAllowed(Tag tag) {
-            return true;
+            // consult the same typeFilters allow-list as getClassForName, so the SnakeYAML 2.x TagInspector
+            // layer actually enforces the configured filters instead of allowing every global tag (CAMEL-24294)
+            return allowTypeFilter(tag.getClassName());
         }
     }
 }

components/camel-snakeyaml/src/test/java/org/apache/camel/component/snakeyaml/SnakeYAMLTypeFilterHelper.java

@@ -21,6 +21,7 @@
 import org.apache.camel.component.snakeyaml.model.RexPojo;
 import org.apache.camel.component.snakeyaml.model.TestPojo;
 import org.apache.camel.component.snakeyaml.model.UnsafePojo;
+import org.yaml.snakeyaml.composer.ComposerException;
 import org.yaml.snakeyaml.constructor.ConstructorException;
 
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
@@ -57,10 +58,11 @@ static void testTypeConstructor(ProducerTemplate template) {
                         "!!org.apache.camel.component.snakeyaml.model.UnsafePojo {name: Camel}"),
                 "As SnakeYAML filters class is can unmarshall, UnsafePojo should not be allowed");
 
-        // Wrapped by SnakeYAML
-        assertTrue(ex.getCause() instanceof ConstructorException);
-        // Thrown by SnakeYAMLDataFormat
-        assertTrue(ex.getCause().getCause() instanceof IllegalArgumentException);
+        // Rejected by the SnakeYAML TagInspector allow-list during composing (CAMEL-24294), before
+        // getClassForName would run - so the failure is a ComposerException, not the previous
+        // ConstructorException -> IllegalArgumentException chain.
+        assertTrue(ex.getCause() instanceof ComposerException);
+        assertTrue(ex.getCause().getMessage().contains("UnsafePojo"));
     }
 
     static void testTypeConstructorFromDefinition(ProducerTemplate template) {
@@ -88,10 +90,9 @@ static void testTypeConstructorFromDefinition(ProducerTemplate template) {
                         "!!org.apache.camel.component.snakeyaml.model.UnsafePojo {name: Camel}"),
                 "As SnakeYAML filters class is can unmarshall, UnsafePojo should not be allowed");
 
-        // Wrapped by SnakeYAML
-        assertTrue(ex.getCause() instanceof ConstructorException);
-        // Thrown by SnakeYAMLDataFormat
-        assertTrue(ex.getCause().getCause() instanceof IllegalArgumentException);
+        // Rejected by the SnakeYAML TagInspector allow-list during composing (CAMEL-24294)
+        assertTrue(ex.getCause() instanceof ComposerException);
+        assertTrue(ex.getCause().getMessage().contains("UnsafePojo"));
     }
 
     static void testAllowAllConstructor(ProducerTemplate template) {

docs/user-manual/modules/ROOT/pages/camel-4x-upgrade-guide-4_22.adoc

@@ -1495,6 +1495,16 @@ data format and the iterator/splitter modes. The full, unmodified entry name rem
 so routes that intentionally recreate the archive's directory structure keep working — read it
 from `CamelTarFileEntryName` for tar and from `zipFileName` for zip instead of `CamelFileName`.
 
+=== camel-snakeyaml - typeFilters are now also enforced by the SnakeYAML TagInspector
+
+When `typeFilters` (or `unmarshalType`) is configured, the allow-list is now also enforced by the
+SnakeYAML 2.x `TagInspector` layer, not only by the `getClassForName` constructor override. A YAML
+document that references a disallowed global tag is therefore rejected earlier, during composing, and
+surfaces as an `org.yaml.snakeyaml.composer.ComposerException` (`"Global tag is not allowed: ..."`)
+instead of the previous `ConstructorException` caused by an `IllegalArgumentException`. The set of
+accepted types is unchanged; only the exception raised for a rejected type differs. Routes that do not
+configure `typeFilters` are unaffected.
+
 === camel-jfr
 
 `camel-jfr` can now also emit JFR events during message routing, in addition to the
@@ -1507,4 +1517,4 @@ read once while the `CamelContext` initializes and cannot be changed afterwards.
 
 `org.apache.camel.spi.StartupStepRecorder` gained the default methods
 `isRuntimeEnabled()` and `setRuntimeEnabled(boolean)`. Both have no-op defaults, so
-existing implementations continue to compile and behave as before.
+existing implementations continue to compile and behave as before.