diff --git a/tests/tests/security/jni/Android.mk b/tests/tests/security/jni/Android.mk
index 363ed47..ecbe43d 100644
--- a/tests/tests/security/jni/Android.mk
+++ b/tests/tests/security/jni/Android.mk
@@ -22,24 +22,25 @@
 LOCAL_MODULE_TAGS := optional
 
 LOCAL_SRC_FILES := \
-		CtsSecurityJniOnLoad.cpp \
-		android_security_cts_CharDeviceTest.cpp \
-		android_security_cts_KernelSettingsTest.cpp \
-		android_security_cts_LinuxRngTest.cpp \
-		android_security_cts_NativeCodeTest.cpp \
-		android_security_cts_SELinuxTest.cpp \
-		android_security_cts_MMapExecutableTest.cpp \
-		android_security_cts_EncryptionTest.cpp \
+                CtsSecurityJniOnLoad.cpp \
+                android_security_cts_CharDeviceTest.cpp \
+                android_security_cts_KernelSettingsTest.cpp \
+                android_security_cts_LinuxRngTest.cpp \
+                android_security_cts_NativeCodeTest.cpp \
+                android_security_cts_SELinuxTest.cpp \
+                android_security_cts_MMapExecutableTest.cpp \
+                android_security_cts_EncryptionTest.cpp \
+                android_security_cts_cve_2021_0394.cpp \
 
 LOCAL_SHARED_LIBRARIES := \
-		libnativehelper \
-		liblog \
-		libcutils \
-		libcrypto \
-		libselinux \
-		libc++ \
-		libpcre2 \
-		libpackagelistparser
+                libnativehelper \
+                liblog \
+                libcutils \
+                libcrypto \
+                libselinux \
+                libc++ \
+                libpcre2 \
+                libpackagelistparser
 
 LOCAL_C_INCLUDES += ndk/sources/cpufeatures
 LOCAL_STATIC_LIBRARIES := cpufeatures
diff --git a/tests/tests/security/jni/CtsSecurityJniOnLoad.cpp b/tests/tests/security/jni/CtsSecurityJniOnLoad.cpp
index 2014591..92d8a4c 100644
--- a/tests/tests/security/jni/CtsSecurityJniOnLoad.cpp
+++ b/tests/tests/security/jni/CtsSecurityJniOnLoad.cpp
@@ -25,6 +25,7 @@
 extern int register_android_security_cts_SeccompTest(JNIEnv*);
 extern int register_android_security_cts_MMapExecutableTest(JNIEnv* env);
 extern int register_android_security_cts_EncryptionTest(JNIEnv* env);
+extern int register_android_security_cts_cve_2021_0394(JNIEnv* env);
 
 jint JNI_OnLoad(JavaVM *vm, void *reserved) {
     JNIEnv *env = NULL;
@@ -61,5 +62,9 @@
         return JNI_ERR;
     }
 
+    if (register_android_security_cts_cve_2021_0394(env)) {
+        return JNI_ERR;
+    }
+
     return JNI_VERSION_1_4;
 }
diff --git a/tests/tests/security/jni/android_security_cts_cve_2021_0394.cpp b/tests/tests/security/jni/android_security_cts_cve_2021_0394.cpp
new file mode 100644
index 0000000..a858894
--- /dev/null
+++ b/tests/tests/security/jni/android_security_cts_cve_2021_0394.cpp
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include <jni.h>
+#include <string.h>
+
+static constexpr char kDefaultValue = 'x';
+static constexpr size_t kStringLength = 4096;
+
+jboolean android_security_cts_cve_2021_0394_poc(JNIEnv* env, jobject thiz) {
+    char array[kStringLength];
+    memset(array, kDefaultValue, kStringLength - 1);
+    array[kStringLength - 1] = 0;
+    jstring s = env->NewStringUTF(array);
+    jboolean isVulnerable = false;
+    char invalidChars[] = { '\xc0', '\xe0', '\xf0' };
+    for (int c = 0; c < sizeof(invalidChars) / sizeof(char); ++c) {
+        char invalid = invalidChars[c];
+        array[kStringLength - 2] = invalid;
+        s = env->NewStringUTF(array);
+        const char* UTFChars = env->GetStringUTFChars(s, nullptr);
+        if (UTFChars[kStringLength - 2] != '?') {
+            isVulnerable = true;
+        }
+        env->ReleaseStringUTFChars(s, UTFChars);
+    }
+    return isVulnerable;
+}
+
+static JNINativeMethod gMethods[] = { { "poc", "()Z",
+        (void*) android_security_cts_cve_2021_0394_poc }, };
+
+int register_android_security_cts_cve_2021_0394(JNIEnv* env) {
+    jclass clazz = env->FindClass("android/security/cts/CVE_2021_0394");
+    return env->RegisterNatives(clazz, gMethods,
+                                sizeof(gMethods) / sizeof(JNINativeMethod));
+}
diff --git a/tests/tests/security/src/android/security/cts/CVE_2021_0394.java b/tests/tests/security/src/android/security/cts/CVE_2021_0394.java
new file mode 100644
index 0000000..325e7af
--- /dev/null
+++ b/tests/tests/security/src/android/security/cts/CVE_2021_0394.java
@@ -0,0 +1,38 @@
+/**
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * 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 android.security.cts;
+
+import android.platform.test.annotations.SecurityTest;
+import org.junit.Test;
+import junit.framework.TestCase;
+
+public class CVE_2021_0394 extends TestCase {
+    static {
+        System.loadLibrary("ctssecurity_jni");
+    }
+
+    /**
+     * b/172655291
+     */
+    @SecurityTest(minPatchLevel = "2021-03")
+    @Test
+    public void testPocCVE_2021_0394() throws Exception {
+        assertFalse(poc());
+    }
+
+    public static native boolean poc();
+}