Secure Sharing PHI PCI PII information in-Android app using Content Provider

1. Secure Sharing PHI/PII/PCI data in Andorid Apps Using Content Provider
Content providers helps an application to manage access to data stored by itself, stored by other
apps, and provide a way to share data with other apps. They encapsulate the data, and provide
mechanisms for defining data security. Content providers is a standard interface that connects data
in one process with code running in another process. Implementing a content provider has many
advantages. One of the major advantages is that it helps to share data across applications in a secure
manner.
As per the implementation from google an application data is very private of itself and hence its
not possible for any other application to access this data by default. Content Provider can use
simple insert, update methods to access application data. Content providers offer granular control
over the permissions for accessing data. You can choose to restrict access to a content provider
from solely within your application, grant blanket permission to access data from other
applications, or configure different permissions for reading and writing data
Private Content Provider is the Content Provider which is used only in the single application,
and the safest Content Provider.
Points (Creating a Content Provider):
1. Do not (Cannot) implement Private Content Provider in Android 2.2 (API Level 8) or earlier.
2. Explicitly set the exported attribute to false.

2. 3. Handle the received request data carefully and securely, even though the data comes from the
same application.
4. Sensitive information can be sent since it is sending and receiving all within the same
application.
5. Sensitive information can be sent since the destination provider is in the same application.
6. Handle received result data carefully and securely, even though the data comes from the same
application.
Public Content Provider is the Content Provider which is supposed to be used by unspecified
Points (Creating a Content Provider):
1. Explicitly set the exported attribute to true.
2. Handle the received request data carefully and securely.
3. When returning a result, do not include sensitive information.
4. Do not send sensitive information.
5. When receiving a result, handle the result data carefully and securely.
Attacks on Content Provider can lead to the following vulnerabilities:
1. SQL injections
2. Data leakage
3. Path Traversal
1. SQL Injections:- Protecting against malicious input-
 If the data managed by the content provider is in an SQL database, including external
untrusted data into raw SQL statements can lead to SQL injection. When accessing a content
provider, use parameterized query methods such as query(), update(), and delete() to avoid
potential SQL injection from untrusted sources.

3. Consider this selection clause:
// Constructs a selection clause by concatenating the user's input to the column name
String mSelectionClause = "var = " + mUserInput;
If you do this, you're allowing the user to concatenate malicious SQL onto your SQL statement.
For example, the user could enter "nothing; DROP TABLE *;" for mUserInput, which would result
in the selection clause var = nothing; DROP TABLE *;. Since the selection clause is treated as an
SQL statement, this might cause the provider to erase all of the tables in the underlying SQLite
database (unless the provider is set up to catch SQL injectionattempts).
To avoid this problem, use a selection clause that uses ? as a replaceable parameter and a separate
array of selection arguments. When you do this, the user input is bound directly to the query rather
than being interpreted as part of an SQL statement. Because it's not treated as SQL, the user input
can't inject malicious SQL. Instead of using concatenation to include the user input, use this
selection clause:
// Constructs a selection clause with a replaceable parameter
String mSelectionClause = "var = ?";
Set up the array of selection arguments like this:
// Defines an array to contain the selection arguments
String[] selectionArgs = {""};
Put a value in the selection arguments array like this:
// Sets the selection argument to the user's input
selectionArgs[0] = mUserInput;
A selection clause that uses ? as a replaceable parameter and an array of selection arguments array
are preferred way to specify a selection, even if the provider isn't based on an SQL database.
2. Data Leakage
Limit the accessibility of an app's sensitive content provider. Use signature permission to
prevent other apps not developed by you from communicating with your app. If you are
using a content provider for sharing data between only your own apps, it is preferable to use
the android:protectionLevel attribute set to “signature” protection. If your content provider is
just for your app’s use then set it to be android:exported=false in the manifest. If you are
intentionally exporting the content provider then you should also specify one or more
permissions for reading and writing.

4. Path Traversal
By using the canonicalized path, directory traversal will be mitigated even when a doubly-encoded
path is supplied. Applications should ensure that any URL received by a content provider is
canonicalized to avoid a directory traversal attack.
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Avinash Sinha: - Lead Security Penetration Tester with one of the largest Healthcare company
Having a demonstrated history of working in the information technology and services industry.
Skilled in Penetration Testing, Vulnerability Assessments, Project Management, Health Care, IoT,
Payment Card Industry Data Security Standard (PCI DSS), Linux, HIPPA, FDA, Information
Security, and Integration. Strong Emphasis on Enterprise Security and information technology
with a Corporate-PGDBA focused in International Business from Symbiosis.