Making Authentication More Secure

Transcript

1. JULIA POTAPENKO
   MAKING
   AUTHENTICATION
   MORE SECURE
   

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2. JULIA POTAPENKO
   • Lead iOS Engineer at Stuzo
   • Security Engineer
   • Mobile Lead at WWCode Kyiv
   • Co-organizer of OWASP Zhytomyr
   • Speaker at OWASP, CocoaHeads,
   WWCode and WTM events
   

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3. WE WILL TALK ABOUT
   ★ What can go wrong before you start coding
   ★ Top common mistakes of iOS engineers
   ★ Frictionless local authentication
   

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4. BEFORE CODING BEGINS
   

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5. BEFORE CODING BEGINS
   

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6. BEFORE CODING BEGINS
   your
   

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7. SDLC
   SOFTWARE DEVELOPMENT LIFE CYCLE
   Requirements definition
   Design
   Development
   Testing
   Deployment
   Maintenance
   You are here
   

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9. SDLC
   SOFTWARE DEVELOPMENT LIFE CYCLE
   Requirements definition
   Design
   Development
   Testing
   Deployment
   Maintenance
   You are here
   

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10. SDLC
    SOFTWARE DEVELOPMENT LIFE CYCLE
    Requirements definition
    Design
    Development
    Testing
    Deployment
    Maintenance
    You are here
    S-
    SECURE
    

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11. SDLC
    SOFTWARE DEVELOPMENT LIFE CYCLE
    Requirements definition
    Design
    Development
    Testing
    Deployment
    Maintenance
    You are here
    S-
    SECURE
    Security training
    

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12. SDLC
    SOFTWARE DEVELOPMENT LIFE CYCLE
    Requirements definition
    Design
    Development
    Testing
    Deployment
    Maintenance
    You are here
    S-
    SECURE
    Security training
    + security requirement
    + risk assessment
    

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13. SDLC
    SOFTWARE DEVELOPMENT LIFE CYCLE
    Requirements definition
    Design
    Development
    Testing
    Deployment
    Maintenance
    You are here
    S-
    SECURE
    Security training
    + security requirement
    + risk assessment
    + threat modeling
    + secure design review
    

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14. RISKS
    IT IS NOT ONLY ABOUT MONEY AND HACKERS
    

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15. RISKS
    • Legal Responsibility
    • Reputation Risks
    • Operations Risks
    • Competitors
    IT IS NOT ONLY ABOUT MONEY AND HACKERS
    

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16. RISKS
    • Legal Responsibility
    • Reputation Risks
    • Operations Risks
    • Competitors
    IT IS NOT ONLY ABOUT MONEY AND HACKERS
    http://www.enforcementtracker.com/
    

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17. EXAMPLE. USER REGISTRATION
    

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18. EXAMPLE. USER REGISTRATION
    1. Enter phone number
    
    

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19. EXAMPLE. USER REGISTRATION
    1. Enter phone number
    
    2. Enter OTP
    
    

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20. EXAMPLE. USER REGISTRATION
    1. Enter phone number
    
    2. Enter OTP
    
    3. Accept TC & PP
    

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21. EXAMPLE. USER REGISTRATION
    1. Enter phone number
    
    2. Enter OTP
    
    3. Accept TC & PP
    

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22. “THE PROBLEM IS NOT ON OUR SIDE”
    

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23. OWASP MASVS
    MASVS (Mobile Application Security Verification Standard)
    
    

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24. OWASP MASVS
    MASVS (Mobile Application Security Verification Standard)
    
    • ARCHITECTURE, DESIGN AND THREAT MODELING
    • DATA STORAGE AND PRIVACY
    • CRYPTOGRAPHY
    • AUTHENTICATION AND SESSION MANAGEMENT
    • NETWORK COMMUNICATION
    • ENVIRONMENTAL INTERACTION
    • CODE QUALITY AND BUILD SETTINGS
    • RESILIENCY AGAINST REVERSE ENGINEERING
    

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25. OWASP MASVS
    MASVS (Mobile Application Security Verification Standard)
    
    • ARCHITECTURE, DESIGN AND THREAT MODELING
    • DATA STORAGE AND PRIVACY
    • CRYPTOGRAPHY
    • AUTHENTICATION AND SESSION MANAGEMENT
    • NETWORK COMMUNICATION
    • ENVIRONMENTAL INTERACTION
    • CODE QUALITY AND BUILD SETTINGS
    • RESILIENCY AGAINST REVERSE ENGINEERING
    

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26. MASVS LEVELS
    

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27. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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28. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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29. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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30. BAD JWT TOKEN EXAMPLE
    https://jwt.io/
    

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31. View Slide

32. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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33. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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34. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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35. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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36. MASVS. AUTHENTICATION. LEVEL 1.
    Description
    4.1
    If the app provides users access to a remote service, some form of
    authentication, such as username/password authentication, is performed at the
    remote endpoint.
    4.2
    If stateful session management is used, the remote endpoint uses randomly
    generated session identifiers to authenticate client requests without sending the
    user's credentials.
    4.3 If stateless token-based authentication is used, the server provides a token that
    has been signed using a secure algorithm.
    4.4 The remote endpoint terminates the existing session when the user logs out.
    4.5 A password policy exists and is enforced at the remote endpoint.
    4.6 The remote endpoint implements a mechanism to protect against the
    submission of credentials an excessive number of times.
    4.7
    Sessions are invalidated at the remote endpoint after a predefined period of
    inactivity and access tokens expire.
    

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37. MASVS. AUTHENTICATION. LEVEL 2.
    Description
    4.8
    Biometric authentication, if any, is not event-bound (i.e. using an API that
    simply returns "true" or "false"). Instead, it is based on unlocking the keychain.
    4.9 A second factor of authentication exists at the remote endpoint and the 2FA
    requirement is consistently enforced.
    4.10 Sensitive transactions require step-up authentication.
    4.11
    The app informs the user of all login activities with their account. Users are able
    view a list of devices used to access the account, and to block specific
    devices.
    

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38. MASVS. AUTHENTICATION. LEVEL 2.
    Description
    4.8
    Biometric authentication, if any, is not event-bound (i.e. using an API that
    simply returns "true" or "false"). Instead, it is based on unlocking the keychain.
    4.9 A second factor of authentication exists at the remote endpoint and the 2FA
    requirement is consistently enforced.
    4.10 Sensitive transactions require step-up authentication.
    4.11
    The app informs the user of all login activities with their account. Users are able
    view a list of devices used to access the account, and to block specific
    devices.
    

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41. WARNING
    

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43. A BETTER WAY TO DO IT
    

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44. A BETTER WAY TO DO IT
    

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45. WHAT THE CODE LOOKS LIKE IN DISASSEMBLER?
    

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46. MASVS. AUTHENTICATION. LEVEL 2.
    Description
    4.8
    Biometric authentication, if any, is not event-bound (i.e. using an API that
    simply returns "true" or "false"). Instead, it is based on unlocking the keychain.
    4.9 A second factor of authentication exists at the remote endpoint and the 2FA
    requirement is consistently enforced.
    4.10 Sensitive transactions require step-up authentication.
    4.11
    The app informs the user of all login activities with their account. Users are able
    view a list of devices used to access the account, and to block specific
    devices.
    

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47. 2FA FLOW
    

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48. 2FA FLOW
    Lets connect
    the requests
    

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49. 2FA FLOW
    

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50. MASVS. AUTHENTICATION. LEVEL 2.
    Description
    4.8
    Biometric authentication, if any, is not event-bound (i.e. using an API that
    simply returns "true" or "false"). Instead, it is based on unlocking the keychain.
    4.9 A second factor of authentication exists at the remote endpoint and the 2FA
    requirement is consistently enforced.
    4.10 Sensitive transactions require step-up authentication.
    4.11
    The app informs the user of all login activities with their account. Users are able
    view a list of devices used to access the account, and to block specific
    devices.
    

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51. DIGITAL SIGNATURE / TRANSACTION SIGNING
    • Key exchange
    • Client creates private, public key pair
    • Private key is stored in Secure Enclave
    • Public key is sent to the Server
    • When transaction is initialized on the client side
    • Client computes hash from transaction data
    • Client encrypts hash with its private key to compute signature
    • Client attaches signature to the transaction data and sends to the Server
    • Server side validation
    • Server receives signed transaction data from the Client
    • Server separates transaction data from the signature
    • Server decrypts signature with public key received from the Client to get hash value
    • Server computes transaction data hash and compares it to the decrypted hash
    

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52. View Slide

53. MASVS. AUTHENTICATION. LEVEL 2.
    Description
    4.8
    Biometric authentication, if any, is not event-bound (i.e. using an API that
    simply returns "true" or "false"). Instead, it is based on unlocking the keychain.
    4.9 A second factor of authentication exists at the remote endpoint and the 2FA
    requirement is consistently enforced.
    4.10 Sensitive transactions require step-up authentication.
    4.11
    The app informs the user of all login activities with their account. Users are able
    view a list of devices used to access the account, and to block specific
    devices.
    

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54. MASVS. AUTHENTICATION. LEVEL 2.
    Description
    4.8
    Biometric authentication, if any, is not event-bound (i.e. using an API that
    simply returns "true" or "false"). Instead, it is based on unlocking the keychain.
    4.9 A second factor of authentication exists at the remote endpoint and the 2FA
    requirement is consistently enforced.
    4.10 Sensitive transactions require step-up authentication.
    4.11
    The app informs the user of all login activities with their account. Users are able
    view a list of devices used to access the account, and to block specific
    devices.
    Architecture
    matters
    

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55. OWASP MOBILE TOP 10
    

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56. OWASP MOBILE TOP 10
    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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57. OWASP MOBILE TOP 10
    ~ Biometrics
    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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58. TOUCH ID AND FACE ID
    LOCAL AUTHENTICATION
    

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59. LOCAL AUTHENTICATION
    • Biometry is stored on device as mathematical representation
    • It is encrypted with a private key stored in Secure Enclave
    • Biometry data is used by Secure Enclave only
    • It can’t be accessed by OS or any application
    

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60. SECURE ENCLAVE
    CREATE AN EXTRA LAYER
    OF SECURITY FOR YOUR
    PRIVATE KEYS.
    • A part of A7 and newer chips
    • Secure Enclave Processor (SEP)
    is separate from Application
    Processor (AP)
    • SEP has its own OS
    

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63. KEYCHAIN
    • A database storing encrypted items
    • Good for storing passwords, tokens, not for files
    • Each item is protected by passcode/biometry and device
    secret
    • Keychain items are available when user authenticates to the
    device
    • To work with Keychain specify a particular policy and user
    message
    

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64. KEYCHAIN
    • A database storing encrypted items
    • Good for storing passwords, tokens, not for files
    • Each item is protected by passcode/biometry and device
    secret
    • Keychain items are available when user authenticates to the
    device
    • To work with Keychain specify a particular policy and user
    message
    WARNING
    

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66. .biometryCurrentSet
    

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68. LONG STORY SHORT
    ★ Frida + Objection
    https://medium.com/securing/pentesting-ios-apps-without-jailbreak-91809d23f64e
    

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70. LETS DESIGN A FRICTIONLESS AUTHENTICATION EXAMPLE
    As a user, when I’m about to pay for the product in the
    mobile app, I should be prompt to a step-up authentication
    and my transaction should be secured.
    REQUIREMENT
    

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71. LETS DESIGN A FRICTIONLESS AUTHENTICATION EXAMPLE
    • Step-up authentication. Validate user password before sending transaction data
    • User can enter password or use biometrics instead
    ▸ To use biometrics we need to store user password in a Keychain
    ▸ We store user password encrypted with a private key stored in
    Secure Enclave
    • Send password to the Backend to validate. If it is correct the Backend will
    send one-time transaction session token
    • Secure the transaction. Use session and digital signature
    • Use one-time session token in transaction request
    • Add digital signature to transaction data
    ▸ Use private key stored in Secure Enclave to generate a public key
    for the Backend and to sign the transactions
    DESIGN
    

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73. WHERE TO GO NEXT
    OWASP MSTG – Testing Local Authentication
    https://github.com/OWASP/owasp-mstg/blob/master/Document/0x06f-Testing-Local-
    Authentication.md
    iOS Security Guide
    https://www.apple.com/business/site/docs/iOS_Security_Guide.pdf
    WWDC 14 – Keychain and Authentication with Touch ID
    https://devstreaming-cdn.apple.com/videos/wwdc/
    2014/711xx6j5wzufu78/711/711_keychain_and_authentication_with_touch_id.pdf
    David Lindner – Don’t Touch Me That Way
    https://nvisium.com/blog/2016/06/22/dont-touch-me-that-way.html
    

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74. https://speakerdeck.com/julep/
    owasp-mstg-in-real-life
    https://speakerdeck.com/julep/owasp-
    mstg-when-authentication-goes-wrong
    OTHER TALKS
    https://www.facebook.com/julia.potapenko.16
    https://t.me/OWASP_ZHYTOMYR_CHAT
    https://speakerdeck.com/julep/
    touch-id-and-face-id-is-it-secure
    https://www.facebook.com/wwcodekyiv
    

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75. THANK YOU!
    

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