Exported Android Components

← Improper Platform Usage

exported_android_components   MEDIUM

Description

Activities/services/receivers exported with no permission checks.

How it works

Activities, receivers, and services are exported with no permission guard, so any installed app (or adb/drozer) can start them directly and reach privileged flows. This is a manifest-level flaw. On Android, DVMA declares an exported AdminActivity, and this screen starts it in-process by component name (the same startActivity path adb, drozer, or a separate app would hit) and reads back the caller it recorded, reaching an internal-only screen with no permission guard.

How to exercise it. DVMA is the harness - open this module from the home index and tap the demo action. The screen ships the malicious input and simulates the attacker (e.g. the companion app, crafted intent, or scanned payload) in-process, and the evidence panel prints the proof. The Tools (optional) and Attack inputs below are only needed to reproduce the exploit end-to-end on a real device.

Exploit steps

1. Set up. Build DVMA with a flavor that enables the Improper Platform Usage category (e.g. --dart-define-from-file=config/flavors/dev.json) and run on an Android emulator you control. The demo needs no external tooling; for the optional on-device reproduction the relevant tools are: adb, drozer, apktool, jadx.
2. Locate the target. From the home index, open Exported Android Components (exported_android_components). The How it works section above describes this module’s specific weakness; the screen states the intended-secure behavior and exposes the vulnerable action.
3. Exploit. From a co-resident/attacker context (adb shell am start/drozer, or a crafted deep link / QR), send the untrusted input to the exported component or WebView and confirm the app performs the unsafe action (navigation, JS execution, file/URI access) with no validation.
4. Observe the evidence. Trigger the vulnerable action and read the evidence panel - it prints the concrete proof (leaked value, accepted replay, executed payload, or unauthorized result).
5. Contrast with the secure path. Run the module’s secure/hardened action (where provided) and confirm the same attack is rejected - this is what a correct implementation should do.
6. Map it back. Cross-reference the MASTG v2 test(s) MASTG-TEST-0364, MASTG-TEST-0365, MASTG-TEST-0366 for the canonical procedure and remediation.

Tools (optional)

• adb
• drozer
• apktool
• jadx