Workshop: Secure Software Development: From Rookie to Hardcore in 90 Minutes

demo project:
https://github.com/vixentael/ios-datasec-basics

1. Intro (Apple, OWASP, jailbreaks)
2. Secure software development lifecycle
3. Stored data mistakes: key management and encryption
4. Practice time
5. Other data security things (network, logging, screenshots)
6. Reading list

Other talks and videos:
https://github.com/vixentael/my-talks

Transcript

1. Secure software development:
   from rookie to hardcore in 90 minutes
   iOS data security workshop
   @vixentael
   

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2. Secure software development:
   from rookie to hardcore in 90 minutes
   iOS data security workshop
   @vixentael
   
   

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3. @vixentael
   product engineer in security
   and cryptography
   started from iOS 3
   OSS maintainer: Themis, Acra
   conduct workshops & training about
   secure apps development
   training.cossacklabs.com
   

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4. https://medium.com/@vixentael/popular-note-taking-apps-share-
   these-security-flaws-security-tips-for-developers-326180e41329 @vixentael
   

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5. https://github.com/vixentael/
   ios-datasec-basics
   @vixentael
   

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6. Plan for next 85 mins:
   1. Intro (Apple, OWASP, jailbreaks)
   @vixentael
   2. Secure software development lifecycle
   3. Stored data mistakes: key management and encryption
   4. Practice time
   5. Other data security things (network, logging, screenshots)
   6. Reading list
   

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7. Secure software development
   Apple (guidelines, rejection guides)
   users (upset, angry)
   money (breaches, legal actions, fines)
   why care anyway?
   @vixentael
   

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8. http://headway.io/blog/apple-app-store-new-
   privacy-policy-what-you-need-to-know/
   New App Store privacy policy
   - minimize the data you collect
   - be transparent on how you use the data
   - protect stored and transit data
   - remove data fully and quickly
   @vixentael
   

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9. GDPR
   @vixentael
   Article 32/35: responsibly store and process
   data according to risks

   

   Article 33/34: detecting data leakage and
   alert users & controller
   https://gdpr-info.eu/
   

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10. @vixentael
    https://gdpr-info.eu/
    Article 32
    

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11. OWASP Top-10 mobile risks
    www.owasp.org/index.php/OWASP_Mobile_Security_Project @vixentael
    • M1: Improper Platform Usage
    • M2: Insecure Data Storage
    • M3: Insecure Communication
    • M4: Insecure Authentication
    • M5: Insufficient Cryptography
    • M6: Insecure Authorization
    • M7: Client Code Quality
    • M8: Code Tampering
    • M9: Reverse Engineering
    • M10: Extraneous Functionality
    

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12. OWASP Top-10 mobile risks
    • M1: Improper Platform Usage
    • M2: Insecure Data Storage
    • M3: Insecure Communication
    • M4: Insecure Authentication
    • M5: Insufficient Cryptography
    • M6: Insecure Authorization
    • M7: Client Code Quality
    • M8: Code Tampering
    • M9: Reverse Engineering
    • M10: Extraneous Functionality
    www.owasp.org/index.php/OWASP_Mobile_Security_Project @vixentael
    

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13. Remote jailbreak iOS11 (patched in iOS12)
    https://twitter.com/kevin_backhouse/status/1057352656560287746 @vixentael
    

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14. www.apple.com/business/site/docs/iOS_Security_Guide.pdf @vixentael
    95 pages PDF
    

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15. Most users trust sensitive data
    to your app regardless of
    how well you protect it.
    

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16. Secure development lifecycle
    methodology
    MS SDL OWASP S-SDLC
    microsoft.com/en-us/sdl owasp.org/index.php/
    OWASP_Secure_Software_Develop
    ment_Lifecycle_Project
    @vixentael
    

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17. Define sensitive data
    Design & implement
    security controls
    Verify security controls

    (testing, monitoring)
    SSDLC in a simple words
    @vixentael
    @vixentael
    during planning
    during planning &
    implementation
    acceptance testing / QA,
    unit testing
    during planning
    during planning &
    implementation
    acceptance testing / QA,
    unit testing
    

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18. @vixentael
    @vixentael
    SSDLC in a simple words
    Define sensitive data
    Design & implement
    security controls
    Verify security controls

    (testing, monitoring)
    during planning
    during planning &
    implementation
    acceptance testing / QA,
    unit testing
    repeat
    

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19. So, one by one
    

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20. Sensitive data
    @vixentael
    @vixentael
    

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21. Sensitive data
    @vixentael
    @vixentael
    geo-locations
    health data
    financial data
    kids locations
    cars remote control
    credentials
    logs
    PII
    

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22. – any kind of data, that will break
    business objectives or prosperity of those
    who use data, if leaked.
    Sensitive data
    @vixentael
    @vixentael
    geo-locations
    health data
    financial data
    kids locations
    cars remote control
    credentials
    logs
    PII
    

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23. Defining sensitive data:
    sensitive user data (PII, password)
    regulations (GDPR / HIPAA / PCI DSS)
    tech data (keys, logs, accesses)
    https://www.cossacklabs.com/blog/what-we-need-to-encrypt-
    cheatsheet.html @vixentael
    @vixentael
    

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24. @vixentael
    @vixentael
    Security controls
    

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25. Data security
    Application security
    Infrastructure security
    Monitoring
    Intrusion detection
    Vulnerability management
    @vixentael
    Security controls
    proactive and reactive
    

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26. Proactive controls
    Data security encryption
    Access security authentication, firewalls, OS
    Node security
    firewalls, compartmentalization,
    isolation, OS
    @vixentael
    

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27. Data security
    key management, integrity
    checks, authenticated crypto
    Access security
    credential management, access
    logging, jailbans
    Node security code security, monitoring, SIEM
    Reactive controls
    @vixentael
    

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28. Verification, testing
    @vixentael
    @vixentael
    https://github.com/OWASP/owasp-mstg
    OWASP Mobile Security Testing Guide
    https://github.com/OWASP/owasp-masvs
    OWASP Mobile Application Security
    Verification Standard
    

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29. MASVS
    @vixentael
    @vixentael
    

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30. @vixentael
    @vixentael
    SSDLC again
    Define sensitive data
    Design & implement
    security controls
    Verify security controls

    (testing, monitoring)
    during planning
    during planning &
    implementation
    acceptance testing / QA,
    unit testing
    repeat
    

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31. Storage encryption
    and key management
    

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32. File and CoreData encryption
    https://developer.apple.com/documentation/uikit/core_app/
    protecting_the_user_s_privacy/encrypting_your_app_s_files
    NSPersistentStoreFileProtectionKey
    @vixentael
    @vixentael
    

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33. Store encrypted data:
    Encrypt stored data
    UserDefaults
    Files
    Database cells
    Backups
    @vixentael
    @vixentael
    

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34. Symmetric encryption with integrity
    checks and long key
    AES-256-GCM
    Encrypt stored data
    @vixentael
    Use strong encryption
    

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35. Symmetric encryption, mistakes
    @vixentael
    @vixentael
    wrong data scope
    poor encryption flow design
    bad key management
    bad cryptography
    encryption lib mis-use
    

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36. Hashing: md5 vs sha256
    @vixentael
    @vixentael
    https://passwordsgenerator.net/sha256-hash-generator/
    

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37. ☠ md5 ☠ sha1
    bcrypt
    https://dusted.codes/sha-256-is-not-a-secure-
    password-hashing-algorithm
    PBKDF2
    sha256 sha512
    HKDF
    @vixentael
    Wanna hash password?
    Use KDF
    

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38. https://www.raywenderlich.com/129-basic-ios-security-keychain-
    and-hashing @vixentael
    Use KDF
    

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39. https://github.com/OWASP/CheatSheetSeries/blob/master/cheatsheets/
    Password_Storage_Cheat_Sheet.md @vixentael
    should be random
    should be > 10k
    
    Use KDF correctly
    

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40. https://pdos.csail.mit.edu/papers/cryptobugs:apsys14.pdf
    269 CVEs
    from 2011-2014
    17%
    83%
    bugs inside crypto libs
    misuses of crypto libs
    by individual apps
    @vixentael
    

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41. @vixentael
    @vixentael
    Even more mistakes
    XORing != encrypting
    using password as encryption key (without KDF)
    storing keys elsewhere
    use single encryption key for all data/users
    

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42. @vixentael
    @vixentael
    Use encryption
    

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43. @vixentael
    @vixentael
    should be random
    should use KDF(key)
    uses AES CBC, not AES GCM
    padding? salt?
    
    Use encryption correctly
    

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44. Use “boring” crypto libraries
    ★ use strong & audited crypto
    ★ work everywhere
    ★ hide cryptographic details
    ★ hard to mis-use
    ★ have integration with key storage
    @vixentael
    https://speakerdeck.com/vixentael/dont-waste-time-on-learning-
    cryptography-better-use-it-properly
    

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45. Encryption that hard to mis-use
    @vixentael
    @vixentael
    Themis
    

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46. Encryption that hard to mis-use
    @vixentael
    @vixentael
    hides cryptographic details: salt, IV, KDF, padding
    built-in KDF, safe to use passphrase
    uses AES-256-GCM
    Themis
    

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47. Storage Transport
    Multi-
    platform
    themis
    libsodium
    tink
    TLS

    themis
    libsodium
    OTRKit

    libsignal
    Made for one
    platform, some
    ports available
    RNCryptor
    CryptoSwift
    CommonCrypto
    https://www.cossacklabs.com/choose-your-ios-crypto.html
    @vixentael
    @vixentael
    

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48. Key management
    APP TOKENS USER PASSWORDS PUBLIC CERTS
    let apiToken = “63ufHs2E82-cJgsm!djr7-Ks1TTYC4TV”
    let appId = "VK1TTYC4TV"
    let poolId = “us-east-1:r0s3s4r3-r3d-13375p34k"
    var userPass = "qwertyqwerty"
    @vixentael
    

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49. APP FLOW
    BUILT-IN
    Keychain
    - KDF
    - encrypt
    @vixentael
    plist/files
    - encrypt
    - obfuscate
    - calculate
    

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50. Practice time
    

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51. https://github.com/vixentael/
    ios-datasec-basics
    @vixentael
    

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52. Built-in keys
    store as hardcode variable
    store obfuscated in plist, de-obfuscate on start
    store encrypted in plist, decrypt on start
    @vixentael
    

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53. App flow keys
    store as memory variable
    store obfuscated/encrypted in User Defaults
    store in Keychain, protect by Biometrics
    @vixentael
    

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54. https://github.com/vixentael/
    ios-datasec-basics
    @vixentael
    

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55. Other data
    security things
    

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56. Transport encryption
    github.com/ssllabs/research/wiki/SSL-and-TLS-
    Deployment-Best-Practices
    private keys RSA-2048, ECDSA-256
    obtain certificate from reliable CA
    TLS v1.3-v1.2
    use secure cipher suites
    TLS_ECDHE_ECDSA_WITH_AES_
    256_GCM_SHA384
    ✅ enable Forward Secrecy
    ✅ enable HSTS (web)
    . rotate certificates often
    @vixentael
    

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57. SSL pinning
    Moya owasp.org/index.php/Pinning_Cheat_Sheet
    @vixentael
    

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58. Update certificate
    Update app with hardcoded certificate
    Built-in several certificates
    Update from server: build trusted channel
    @vixentael
    SSL pinning
    

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59. transport = Transport()
    transport?.setupKeys(serverId, serverPublicKey: serverPublicKey)
    session = TSSession(userId: clientIdData, privateKey:
    clientPrivateKeyData, callbacks: transport!)
    startSession(clientId: clientId, message: connectionMessage)
    Encrypt over SSL
    Themis
    @vixentael
    

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60. Themis axolotl
    noise
    @vixentael
    Encrypt over SSL
    

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61. medium.com/@AyunasCode/how-to-hide-your-api-keys-367ef6589949
    shanirivers.me/posts/hiding-your-api-keys-for-ios-projects
    orta/cocoapods-keys
    awslabs/git-secrets
    keys.plist → .gitignore
    Do not commit secrets
    @vixentael
    

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62. Do not log secrets
    cfpb/clouseau
    Automate checking
    code for forgotten
    secrets.
    @vixentael
    

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63. @vixentael
    https://speakerdeck.com/vixentael/x-things-you-
    need-to-know-before-implementing-cryptography
    

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64. Do’s and Don’ts

    of secure development
    

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65. DON’T
    - Do things just because “they make security better”
    - Copy-paste from StackOverflow
    - Implement your own security controls where 

    solutions are available
    @vixentael
    

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66. DO
    - Only things that address real valid risks
    - Use industry’s best practices, standards and tools
    - Explain why spending effort is necessary
    - Plan, implement, test, formalize
    - Watch the trends, follow experts
    @vixentael
    

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67. Reading, watching
    

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68. General theory
    http://mashable.com/2016/04/16/apple-security-explained/
    How Apple Security works
    https://medium.com/@vixentael/popular-note-taking-apps-share-these-security-flaws-security-
    tips-for-developers-326180e41329
    Popular note-taking apps share these security flaws
    https://medium.com/@cossacklabs/apple-export-regulations-on-crypto-6306380682e1
    Apple Export Regulations on Cryptography
    https://howhttps.works/
    How HTTPS works: cats
    

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69. Cryptography
    https://www.owasp.org/index.php/Cryptographic_Storage_Cheat_Sheet
    Cryptographic Storage Cheat Sheet
    https://www.owasp.org/index.php/Key_Management_Cheat_Sheet
    Key Management Cheat Sheet
    https://developer.apple.com/library/content/documentation/Security/Conceptual/
    cryptoservices/KeyManagementAPIs/KeyManagementAPIs.html
    Managing Keys, Certificates, and Passwords
    https://cossacklabs.com/choose-your-ios-crypto.html
    Crypto in iOS: choose your destiny
    

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70. Testing
    http://iphonedevwiki.net/index.php/Crack_prevention
    Crack prevention
    https://mobile-security.gitbook.io/mobile-security-testing-guide/ios-testing-guide/0x06a-
    platform-overview
    Mobile Security Testing Guide
    https://github.com/OWASP/owasp-masvs
    OWASP Mobile Application Security Verification Standard
    

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71. Talks & training
    github.com/vixentael/
    my-talks
    training.cossacklabs.com
    

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72. @vixentael
    product engineer in security
    and cryptography
    conduct workshops & training about
    secure apps development
    

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