Malicious Third-Party SDK

← Supply Chain (OWASP Mobile M2)

malicious_third_party_sdk   MEDIUM

Description

A bundled SDK exfiltrates data far beyond its stated purpose.

How it works

A bundled SDK advertised for one benign purpose actually harvests the auth token, clipboard, and keystrokes on init and beacons them to an attacker exfiltration endpoint. A pentester sees the exfil in mitmproxy; jadx reveals the endpoint.

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 Supply Chain (OWASP Mobile M2) category (e.g. --dart-define-from-file=config/flavors/dev.json) and run on an emulator/simulator you control. The demo needs no external tooling; for the optional on-device reproduction the relevant tools are: mitmproxy, Burp Suite, MobSF, JEB · Android: jadx, apktool · iOS: ipsw, class-dump.
2. Locate the target. From the home index, open Malicious Third-Party SDK (malicious_third_party_sdk). 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. Inspect the dependency/SDK surface (lockfiles, bundled SDKs, update channel) and confirm the untrusted or unverified component is accepted - e.g. a substituted package, an unsigned artifact, or a silent post-deploy update.
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-0318, MASTG-TEST-0319 for the canonical procedure and remediation.

Tools (optional)

• mitmproxy
• Burp Suite
• MobSF
• JEB

Android

• jadx
• apktool

iOS

• ipsw
• class-dump