feat: add guidance hook for SpEL injection

MODULE.bazel

@@ -136,6 +136,9 @@ VULNERABLE_TEST_MAVEN_ARTIFACTS = [
     "org.apache.xmlgraphics:batik-xml:1.14",
     "org.glassfish:javax.el:3.0.1-b06",
     "org.hibernate:hibernate-validator:5.2.4.Final",
+    "org.springframework.cloud:spring-cloud-function-context:3.1.6",
+    "org.springframework.cloud:spring-cloud-function-core:3.1.6",
+    "org.springframework:spring-messaging:6.1.4",
 ]
 
 maven = use_extension("@rules_jvm_external//:extensions.bzl", "maven")

examples/BUILD.bazel

@@ -334,6 +334,26 @@ java_fuzz_target_test(
     ],
 )
 
+java_fuzz_target_test(
+    name = "SpringCloudFunctionRoutingFuzzer",
+    srcs = [
+        "src/main/java/com/example/SpringCloudFunctionRoutingFuzzer.java",
+    ],
+    allowed_findings = [
+        "com.code_intelligence.jazzer.api.FuzzerSecurityIssueHigh",
+    ],
+    fuzzer_args = ["-runs=100000"],
+    tags = ["no-jdk8"],
+    target_class = "com.example.SpringCloudFunctionRoutingFuzzer",
+    verify_crash_reproducer = False,
+    deps = [
+        "@maven//:com_fasterxml_jackson_core_jackson_databind",
+        "@maven//:org_springframework_cloud_spring_cloud_function_context",
+        "@maven//:org_springframework_cloud_spring_cloud_function_core",
+        "@maven//:org_springframework_spring_messaging",
+    ],
+)
+
 java_fuzz_target_test(
     name = "JacksonCborFuzzer",
     srcs = [

examples/src/main/java/com/example/SpringCloudFunctionRoutingFuzzer.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2025 Code Intelligence GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import java.util.Arrays;
+import java.util.logging.Level;
+import java.util.logging.LogManager;
+import org.springframework.cloud.function.context.FunctionProperties;
+import org.springframework.cloud.function.context.catalog.SimpleFunctionRegistry;
+import org.springframework.cloud.function.context.config.RoutingFunction;
+import org.springframework.cloud.function.json.JacksonMapper;
+import org.springframework.messaging.Message;
+import org.springframework.messaging.converter.CompositeMessageConverter;
+import org.springframework.messaging.converter.StringMessageConverter;
+import org.springframework.messaging.support.MessageBuilder;
+
+/**
+ * Reproduce <a href="https://spring.io/security/cve-2022-22963">CVE-2022-22963</a> by fuzzing the
+ * routing-expression header in Spring Cloud Function.
+ */
+public class SpringCloudFunctionRoutingFuzzer {
+  private static RoutingFunction router;
+
+  public static void fuzzerInitialize() {
+    LogManager.getLogManager().getLogger("").setLevel(Level.SEVERE);
+    // Empty function registry
+    SimpleFunctionRegistry registry =
+        new SimpleFunctionRegistry(
+            null,
+            new CompositeMessageConverter(Arrays.asList(new StringMessageConverter())),
+            new JacksonMapper(new ObjectMapper()));
+    router = new RoutingFunction(registry, new FunctionProperties());
+  }
+
+  public static void fuzzerTestOneInput(String payload, String expr) {
+    try {
+      Message<String> message =
+          MessageBuilder.withPayload(payload)
+              .setHeader("spring.cloud.function.routing-expression", expr)
+              .build();
+      router.apply(message);
+    } catch (Throwable ignored) {
+      // Most inputs will cause parsing or routing errors; that is fine.
+    }
+  }
+}