Published 2026-11-06 · By Jeffrey Monica
Scope the client, build and backend as separate boundaries
Begin with written permission, build identifier, platform version and two synthetic test identities. Inventory storage, network calls, local permissions, deep links, embedded SDKs, account actions and the backend resources the app can reach. Label every control tested, not tested, blocked by access or excluded. A test matrix is evidence only for included builds and environments.
OWASP MASVS defines mobile security control groups; MASTG supplies techniques. MASVS does not by itself assess backend object authorization. Pair it with independent API tests and never claim an OWASP certification.
Validation checklist
- Record permitted apps, API endpoints and test accounts.
- Keep secrets and customer records out of public test artifacts.
- Record platform-specific assumptions and test limitations.
Storage, cryptography and network behavior
For MASVS-STORAGE, inspect Keychain, Android encrypted storage/Keystore usage, backups, caches, logs and crash events. Check whether tokens, identifiers or personal details survive logout or leak through diagnostics. Protected storage lowers accidental exposure; it does not confer permission to a server resource.
For MASVS-CRYPTO and MASVS-NETWORK, inspect TLS peer validation, weak algorithms, nonce reuse and error recovery. Test expected failures under an intercepted or invalid connection. Certificate pinning needs a rotation and break-glass policy and cannot replace server authorization.
Validation checklist
- Validate transport errors on representative devices.
- Check backups, logs and telemetry for credentials.
- Trace encryption key and nonce lifecycle against a threat model.
Authentication, platform interfaces and executable code
For MASVS-AUTH, test sign-in, refresh rotation, account switching, logout, session revocation and step-up after recovery. Treat Apple App Attest and Google Play Integrity as risk inputs rather than granting API object permissions. For MASVS-PLATFORM, check URL schemes, universal/app links, exported Android components and webview boundaries.
For MASVS-CODE and MASVS-RESILIENCE, verify build and dependency integrity, risky reflection or logging, and expected client-tampering behavior. Assume a determined attacker can modify the client; security-sensitive decisions remain server-side.
Validation checklist
- Test revoked sessions and cross-user API objects.
- Exercise link handlers with untrusted inputs.
- Verify release signing and provenance.
Privacy and retest evidence
For MASVS-PRIVACY, inventory third-party SDK activity and data flows against the app's actual privacy policy and user choices. Avoid claims that any unreviewed SDK is safe. A good handoff maps each finding to an app build, control, evidence, owner, severity rationale, fix and negative-path regression check.
Retest after the fix on representative operating systems and the deployed backend. A successful local unit test does not verify the actual production release or third-party behavior.
Validation checklist
- Record the result and evidence for each control.
- Document residual risks, assumptions and device coverage.
- Never represent partial coverage as official MASVS certification.
Primary references
Engineering practices and threat-model choices, not product certification, a guarantee against compromise or a customer penetration-test result.