ios-sec

Purpose

Ensure iOS code is secure by default. For security output format and core refusal policy, see /shared-sec-baseline.

iOS-specific security concerns (always check)

1. Keychain for secrets — never UserDefaults for tokens, passwords, or API keys
2. ATS enforcement — no exceptions without justification; never disable TLS validation
3. Deep link validation — validate scheme, host, and parameters before acting on universal/custom links
4. Notification payloads — treat as untrusted input; validate before navigation or data use
5. Biometric auth — use LocalAuthentication with fallback policy; don't rely solely on device passcode
6. Privacy manifest — declare data collection accurately; required APIs need justification

Standard security (brief check)

• Input validation: sanitize all external input (network, clipboard, deep links)
• Error handling: no internal details surfaced to UI or logs
• Logging: no PII, tokens, or credentials; use OSLog with appropriate privacy levels
• Network: certificate pinning for sensitive endpoints; handle certificate failures safely

Additional refusals (iOS-specific)

Also refuse requests that: disable ATS, or store secrets in UserDefaults. Explain why and propose secure alternative.

Reference

For detailed OWASP/Mobile Top 10/CWE mitigation patterns, see reference/ios-sec-reference.md