Cleartext Traffic Allowed

← Insecure Communication

cleartext_traffic_allowed   EASY

Description

App sends requests over plain HTTP; cleartext permitted in manifest/plist.

How it works

The app posts credentials to an http:// endpoint, and the platform config permits cleartext (usesCleartextTraffic=true on Android, NSAllowsArbitraryLoads on iOS). It fires a real request; point it at your mitmproxy or listener and the credentials appear verbatim on the wire.

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 Insecure Communication 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, Wireshark, Burp Suite.
2. Locate the target. From the home index, open Cleartext Traffic Allowed (cleartext_traffic_allowed). 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. Route the app through an intercepting proxy (Burp/mitmproxy) with your CA installed, trigger the network call, and confirm you can read or modify traffic (cleartext, weak TLS, or a trivially-bypassed pin).
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-0235, MASTG-TEST-0237, MASTG-TEST-0238, MASTG-TEST-0322, MASTG-TEST-0233 for the canonical procedure and remediation.

Tools (optional)

• mitmproxy
• Wireshark
• Burp Suite

Real-world references

Concrete public disclosures that match this vulnerability class:

• Plain Text, Plain Risks: HTTP Inclusion in Android WebViews at Scale (USENIX Security 2026)