Insecure Password Reset Token / Magic Link

← Insecure Authentication / Authorization

insecure_password_reset_token   MEDIUM

Description

Password-reset tokens / magic-login links are short, predictable, and never expire.

How it works

Reset tokens are short 6-digit values from a seeded, non-secure Random() and never expire. Two tokens issued in sequence are related and guessable, and an old link works forever, so an attacker can brute-force or predict a valid reset link and take over accounts. A secure token is long, drawn from a cryptographically secure random source, and has a short TTL.

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 Authentication / Authorization 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: Burp Suite, mitmproxy, token analysis.
2. Locate the target. From the home index, open Insecure Password Reset Token / Magic Link (insecure_password_reset_token). 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. Drive the authentication/authorization path, capture the token / assertion / decision, then replay or tamper with it (mitmproxy, a WebAuthn test harness, or by editing the value) and confirm the server-side check accepts the manipulated request.
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.

Tools (optional)

• Burp Suite
• mitmproxy
• token analysis