MASTG-TEST-0205 Non-random Sources Usage (Android)

Platform: Android
Weakness: MASWE-0012
Weakness in the numbering of the MASWE beta: MASWE-0027
Profiles: L1 (basic security), L2 (advanced security)
Type: static, code, manual
Prerequisites: identify-sensitive-data, identify-security-relevant-contexts
Knowledge: MASTG-KNOW-0013
Best practices: MASTG-BEST-0001

Overview

Android applications sometimes use non-random sources to generate "random" values, leading to potential security vulnerabilities. Common practices include relying on the current time, such as Date().getTime(), or accessing Calendar.MILLISECOND to produce values that are easily guessable and reproducible.

Steps

Use MASTG-TECH-0013 to reverse engineer the app.
Use MASTG-TECH-0014 to look for the relevant APIs.

Observation

The output should contain a list of locations where non-random sources are used.

Evaluation

The test case fails if you can find security-relevant values, such as passwords or tokens, generated using non-random sources.

Further Validation Required:

Inspect each reported code location using MASTG-TECH-0023 to determine whether the usage is security-relevant:

Determine whether the generated values are used for security-relevant purposes, such as generating cryptographic keys, initialization vectors (IVs), nonces, authentication tokens, session identifiers, passwords, or PINs.

Tickets liés

Liens
Type de lien	Ticket
is related to	MASTG-BEST-0001 Use Secure Random Number Generator APIs (Android)

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