(#) PreferenceActivity should not be exported !!! WARNING: PreferenceActivity should not be exported This is a warning. Id : `ExportedPreferenceActivity` Summary : PreferenceActivity should not be exported Severity : Warning Category : Security Platform : Android Vendor : Android Open Source Project Feedback : https://issuetracker.google.com/issues/new?component=192708 Since : Initial Affects : Kotlin and Java files and manifest files Editing : This check runs on the fly in the IDE editor See : http://securityintelligence.com/new-vulnerability-android-framework-fragment-injection See : https://goo.gle/ExportedPreferenceActivity Implementation : [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-checks/src/main/java/com/android/tools/lint/checks/PreferenceActivityDetector.kt) Tests : [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-tests/src/test/java/com/android/tools/lint/checks/PreferenceActivityDetectorTest.java) Copyright Year : 2014 Fragment injection gives anyone who can send your `PreferenceActivity` an intent the ability to load any fragment, with any arguments, in your process. (##) Example Here is an example of lint warnings produced by this check: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text AndroidManifest.xml:28:Warning: PreferenceActivity should not be exported [ExportedPreferenceActivity] <activity ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Here is the source file referenced above: `AndroidManifest.xml`: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers <?xml version="1.0" encoding="utf-8"?> <!-- ~ Copyright (C) 2014 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. --> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="test.bytecode" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="10" /> <application android:icon="@drawable/ic_launcher" android:label="@string/app_name" > <activity android:name="android.preference.PreferenceActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ You can also visit the [source code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-tests/src/test/java/com/android/tools/lint/checks/PreferenceActivityDetectorTest.java) for the unit tests for this check to see additional scenarios. The above example was automatically extracted from the first unit test found for this lint check, `PreferenceActivityDetector.testWarningWhenImplicitlyExportingPreferenceActivity`. To report a problem with this extracted sample, visit https://issuetracker.google.com/issues/new?component=192708. (##) Suppressing You can suppress false positives using one of the following mechanisms: * Adding the suppression attribute `tools:ignore="ExportedPreferenceActivity"` on the problematic XML element (or one of its enclosing elements). You may also need to add the following namespace declaration on the root element in the XML file if it's not already there: `xmlns:tools="http://schemas.android.com/tools"`. ```xml <?xml version="1.0" encoding="UTF-8"?> <manifest xmlns:tools="http://schemas.android.com/tools"> ... <activity tools:ignore="ExportedPreferenceActivity" .../> ... </manifest> ``` * Using a suppression annotation like this on the enclosing element: ```kt // Kotlin @Suppress("ExportedPreferenceActivity") fun method() { problematicStatement() } ``` or ```java // Java @SuppressWarnings("ExportedPreferenceActivity") void method() { problematicStatement(); } ``` * Using a suppression comment like this on the line above: ```kt //noinspection ExportedPreferenceActivity problematicStatement() ``` * Using a special `lint.xml` file in the source tree which turns off the check in that folder and any sub folder. A simple file might look like this: ```xml <?xml version="1.0" encoding="UTF-8"?> <lint> <issue id="ExportedPreferenceActivity" severity="ignore" /> </lint> ``` Instead of `ignore` you can also change the severity here, for example from `error` to `warning`. You can find additional documentation on how to filter issues by path, regular expression and so on [here](https://googlesamples.github.io/android-custom-lint-rules/usage/lintxml.md.html). * In Gradle projects, using the DSL syntax to configure lint. For example, you can use something like ```gradle lintOptions { disable 'ExportedPreferenceActivity' } ``` In Android projects this should be nested inside an `android { }` block. * For manual invocations of `lint`, using the `--ignore` flag: ``` $ lint --ignore ExportedPreferenceActivity ...` ``` * Last, but not least, using baselines, as discussed [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).