Encryption Without Magic, Risk Management Without Pain

#security #crypto #databases #notmobile #trust #infrastructures #separation-of-duties #echelonization

1. What is attack surface, how cryptography helps to narrow it.
2. Simple crypto-systems, but significant downsides.
3. Middleware-side encryption: protecting data in web-based infrastructures.
4. Client-side encryption: trust to mobile apps and code execution. E2EE. ZKA. ZKP.
5. Echelonization, and traditional techniques.

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If you can't tap on the link inside slides, please open as pdf (button on the right).

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In-depth technical inquiry about cryptography in a wider context: how it helps to narrow more significant risks to controlled attack surfaces, enables managing the risk efficiently and elegantly, how tools and algorithms sit in a broader context of managing infrastructure-wide risks associated with handling sensitive data.

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Links to follow:

12 and 1 ideas how to enhance backend data security
https://medium.com/@cossacklabs/12-and-1-ideas-how-to-enhance-backend-data-security-4b8ceb5ccb88

Explain Like I’m 5: Zero Knowledge Proof
https://hackernoon.com/eli5-zero-knowledge-proof-78a276db9eff

DevOps and security: from trenches to command centers
https://medium.com/@9gunpi/devops-and-security-from-trenches-to-command-centers-466dfb58fe5b

GDPR for engineers
https://www.cossacklabs.com/blog/gdpr-for-engineers.html

Transcript

1. ENCRYPTION WITHOUT
   MAGIC,
   RISK MANAGEMENT
   WITHOUT PAIN
   @vixentael
   

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2. @vixentael Product Engineer
   Feel free to reach me with
   security questions.
   I do check my inbox :)
   

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3. View Slide

4. CRYPTOGRAPHY?
   

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5. CRYPTOGRAPHY?
   AES
   DES
   3DES
   CBC
   CFB
   SEAL
   Salsa20
   RSA
   DSA
   OFB
   Blowfish
   SHARK
   RC4
   DSS
   ECB CTR
   Twofish
   Camelia
   SEED
   Rabbit
   ECDSA
   @vixentael
   

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6. MD5
   SHA1
   SHA256
   HASHING PASSWORDS?
   @vixentael
   

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7. MD5
   SHA1
   SHA256
   HASHING PASSWORDS?
   https://www.owasp.org/index.php/Password_Storage_Cheat_Sheet
   https://dusted.codes/sha-256-is-not-a-secure-password-hashing-algorithm
   HKDF
   bcrypt
   PBKDF2
   @vixentael
   

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8. algorithms
   elliptic curves
   key management
   public key validity
   storing secrets
   CRYPTOGRAPHY
   cool, but… @vixentael
   

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9. crypto is not a
   but a method to manage
   the attack surface
   @vixentael
   

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10. ATTACK SURFACE
    – all the possible places
    where sensitive data may be
    stolen by adversary
    https://www.owasp.org/index.php/Attack_Surface_Analysis_Cheat_Sheet @vixentael
    

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11. it’s easier to monitor
    the suspicious behavior
    in a small place
    @vixentael
    

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12. HANDLING SENSITIVE DATA
    WITH CARE
    avoid plaintext as possible
    manage keys properly
    decrease time of plaintext secrets in memory
    log, monitor and inspect
    @vixentael
    limit access to data
    

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13. – HOW TO MANAGE
    THE ATTACK SURFACE
    OF MY DATA?
    

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14. one container one key
    @vixentael
    symmetric encryption
    with poor key
    management
    

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15. attack surface
    is arbitrary
    one container one key
    symmetric encryption
    with poor key
    management
    key leaked
    → data leaked
    @vixentael
    

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16. https://en.wikipedia.org/wiki/Cryptosystem @vixentael
    

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17. KEY AND TRUST
    MANAGEMENT SHOULD
    REFLECT YOUR SYSTEM
    @vixentael
    

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18. MESSAGING
    https://core.telegram.org/api/end-to-end
    @vixentael
    

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19. GOOD MESSAGING
    IS E2EE
    …but your infrastructures
    are not only for messaging @vixentael
    

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20. NAIVE DATABASE ENCRYPTION
    attack surface
    is almost everywhere
    @vixentael
    

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21. NARROWING ATTACK SURFACE
    middleware-side
    encryption
    client-side
    encryption
    @vixentael
    

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22. View Slide

23. MIDDLEWARE-SIDE
    ENCRYPTION
    

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24. SQL injections
    code injections
    execution flow attacks
    reflection attacks
    XSS
    crypto-miners everywhere
    MitM
    REAL-WORLD WEB SERVER
    @vixentael
    

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25. ATTACK SURFACE IS
    EVERYWHERE :(
    monitor everything
    @vixentael
    REAL-WORLD WEB SERVER
    

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26. TRY SYMMETRIC ENCRYPTION?
    encrypt/decrypt data
    using sym key
    @vixentael
    

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27. encrypt/decrypt data
    using sym key
    easy to steal a key
    https://www.alibabacloud.com/
    help/faq-detail/37505.htm @vixentael
    TRY SYMMETRIC ENCRYPTION?
    

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28. “COMBINED” ENCRYPTION
    @vixentael
    what if no decryption key?
    

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29. “COMBINED” ENCRYPTION
    enc_data = Enc(data, Krand)
    container = (enc_data, PubKweb, enc_key)
    @vixentael
    enc_key = Enc(Krand, PrivKweb, PubKtds)
    

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30. PubKey of ‘trusted
    decryption service’
    @vixentael
    “COMBINED” ENCRYPTION
    

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31. TRUSTED DECRYPTION SERVICE
    decrypts data
    @vixentael
    encrypts data
    

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32. trusted element in
    infrastructure
    SEPARATION OF DUTIES
    no decryption
    keys
    monitor & log
    @vixentael
    

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33. TRUSTED DECRYPTION SERVICE
    @vixentael
    NARROWED ATTACK
    SURFACE
    

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34. monitor everything
    monitor decryption proxy
    @vixentael
    

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35. WHERE TO USE THIS
    TECHNIQUE?
    micro-services infrastructure
    @vixentael
    public-oriented interfaces
    non-trusted client side (browsers, IoT devices)
    hard to store keys securely
    

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36. HOW TO IMPLEMENT?
    ACRA
    https://github.com/cossacklabs/acra
    GREEN SQL
    https://github.com/larskanis/greensql-fw
    HEXATIER
    http://www.hexatier.com/
    ORACLE DATABASE
    FIREWALL / TDE
    http://www.oracle.com/
    @vixentael
    

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37. View Slide

38. CLIENT-SIDE
    ENCRYPTION
    

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39. MOVE TRUST TO CLIENTS
    session hijacking
    unattended backups
    MitM
    replay attacks
    misconfigured ACL
    trusted element in
    infrastructure
    @vixentael
    

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40. P2P TRUST
    system doesn’t know
    anything about data
    encrypted
    containers
    user-generated
    keys
    @vixentael
    

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41. ZERO KNOWLEDGE
    ARCHITECTURES
    @vixentael
    

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42. ZKA is a design principle that
    enables software to provide services
    over protected client data without
    having an unencrypted access to it.
    @vixentael
    

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43. e2ee clients
    @vixentael
    ZKA INCLUDES:
    

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44. e2ee clients
    all operations are on encrypted data:
    – control access to data from different users
    – CRUD
    – search (in encrypted data)
    ZKA INCLUDES:
    @vixentael
    

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45. weak key management
    algorithm weakness
    user pocket
    attack surface
    RISKS FOR ZKA:
    @vixentael
    

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46. WHEN TO USE ZKA?
    trusted client side (mobile, HSM/TPM)
    @vixentael
    

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47. ZKA is already solved for
    specific use-cases or
    in a naive ways
    @vixentael
    

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48. MESSAGING END-TO-END
    ENCRYPTION
    @vixentael
    

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49. AUTHENTICATION ZERO KNOWLEDGE
    PROOF
    https://www.cossacklabs.com/zero-
    knowledge-protocols-without-magic.html
    @vixentael
    

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50. COLLABORATING
    ON DATA
    – store encrypted
    – share with others
    – manage access to
    parties
    ???
    @vixentael
    

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51. naive approach
    – duplications
    – key management
    problems
    SHARING ENCRYPTED DATA
    @vixentael
    

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52. give access to
    certain blocks of
    data to exact users
    github.com/cossacklabs/
    hermes-core
    CRYPTOGRAPHIC ACL
    @vixentael
    

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53. – Key wrapping
    storage keys user keys
    blocks
    HOW TO BUILD IT?
    @vixentael
    

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54. – Key wrapping
    – Manage privileges
    @vixentael
    HOW TO BUILD IT?
    

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55. – Key wrapping
    – Manage privileges
    – Control requests
    @vixentael
    HOW TO BUILD IT?
    

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56. shared
    audit logs complex docs,
    spreadsheets
    config files
    file system
    document store
    protection
    MORE POSSIBLE USE-CASES
    @vixentael
    

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57. HERMES
    https://github.com/cossacklabs/hermes-core
    ZEROKIT
    https://tresorit.com/zerokit
    LAFS
    https://tahoe-lafs.org/trac/tahoe-lafs
    @vixentael
    IMPLEMENTATIONS
    

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58. monitor everything
    monitor client side
    @vixentael
    

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59. MORE GOODIES TO
    THINK ABOUT
    

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60. Cryptography is well implemented,
    if it allows to narrow attack surface,
    and increase control of data.
    @vixentael
    

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61. if the system has
    one perimeter,
    it will fail!
    ECHELONIZATION
    @vixentael
    

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62. #qconlondon @vixentael
    ..add more layers
    of defense
    ECHELONIZATION
    

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63. EXCEPT CRYPTO, YOU ALSO NEED
    log and monitor events
    credential management
    access control, access logging
    firewall, IDS, infrastructure management
    ...
    

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64. 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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65. 2
    RECAP
    

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66. THINGS TO REMEMBER
    1. cryptography aims to narrow the attack surface
    2. choose relevant encryption scheme
    3. combine cryptography and classic security
    techniques
    @vixentael
    4. echelonization, compartmentalization
    

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67. https://medium.freecodecamp.org/preventing-leaks-and-injections-in-your-database-
    be3743af7614
    How to prevent database leaks and injections
    https://medium.com/@cossacklabs/12-and-1-ideas-how-to-enhance-backend-data-
    security-4b8ceb5ccb88
    12 and 1 ideas how to enhance backend data security
    BACKEND SECURITY
    https://www.cossacklabs.com/blog/gdpr-for-engineers.html
    GDPR for engineers: technical requirements
    https://samnewman.io/talks/insecure-transit-microservice-security/
    Insecure Transit - Microservice Security
    

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68. CRYPTOGRAPHY
    https://hackernoon.com/eli5-zero-knowledge-proof-78a276db9eff
    Explain Like I’m 5: Zero Knowledge Proof
    https://www.owasp.org/index.php/Secure_Coding_Cheat_Sheet
    Secure Coding Cheat Sheet
    https://www.owasp.org/index.php/OWASP_Secure_Coding_Practices_-
    _Quick_Reference_Guide
    Secure Coding Practices
    

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69. @vixentael
    cryptographic software,
    security consulting,
    developers training
    github.com/
    vixentael/my-talks
    

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70. IMAGE CREDITS
    www.flaticon.com
    freepik, linector, switficons, pixelperfect, smashicons, icon pond,
    dinosoftlabs
    Authors:
    

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