Upgrade to Pro — share decks privately, control downloads, hide ads and more …

Distill: Death to Cookies

Konstantin Haase
August 09, 2013
Technology
7
1.1k

Distill: Death to Cookies

Konstantin Haase

August 09, 2013
Tweet

More Decks by Konstantin Haase

See All by Konstantin Haase
RubyConf Philippines 2017: Magenta is a Lie
rkh
0
180
How We Replaced Salary Negotiations with a Sinatra App
rkh
17
3.9k
HTTP (RubyMonsters Edition)
rkh
5
900
GCRC 2015: Abstract Thoughts on Abstract Things
rkh
1
330
Frozen Rails: Magenta - The Art Of Abstraction
rkh
3
260
RedDotRubyConf 2014: Magenta is a Lie - and other tales of abstraction
rkh
0
690
Ancient City Ruby: Hack me, if you can!
rkh
2
380
Boston I/O: Continuous Integration
rkh
3
270
Steel City Ruby: Architecting Chaos
rkh
4
800

Other Decks in Technology

See All in Technology
AWS パートナー企業でテクニカルサポートに従事して2年経ったので思うところをまとめてみた
kazzpapa3
3
1.3k
コードを書く隙間を見つけて生きていく技術/Findy 思考の現在地
fujiwara3
22
4.3k
TransitGatewayの基礎
toru_kubota
0
220
インシデントレスポンスのライフサイクルを廻すポイントってなに / Pinpoints of Incidentresponse Lifecycle for Operation
sakaitakeshi
0
280
元インフラエンジニアに成る / Human Resources to Human Relations
bobtani
1
110
日本におけるデータエンジニアリングのこれまでとこれから
foursue
9
1.5k
0→1開発における技術選定において一番大切なこと
bicstone
1
310
クラウドサインにおけるプロダクトマネージャーの役割と開発プロセス / 20240410_cloudsign-PdM
bengo4com
1
660
AWS を使う上で知っておきたいオンプレミス知識/aws-on-premise-essentials
emiki
1
4.1k
検証を通して見えてきたTiDBの性能特性
lycorptech_jp
PRO
3
1k
Signals Unleashed: The Full Guide
rainerhahnekamp
0
350
SPI原点回帰論：事業課題とFour Keysの結節点を見出す実践的ソフトウェアプロセス改善 / DevOpsDays Tokyo 2024
visional_engineering_and_design
4
970

Featured

See All Featured
Art, The Web, and Tiny UX
lynnandtonic
288
19k
Facilitating Awesome Meetings
lara
40
5.6k
Dealing with People You Can't Stand - Big Design 2015
cassininazir
355
22k
Teambox: Starting and Learning
jrom
127
8.4k
Debugging Ruby Performance
tmm1
69
11k
Stop Working from a Prison Cell
hatefulcrawdad
265
19k
Imperfection Machines: The Place of Print at Facebook
scottboms
258
12k
How to name files
jennybc
64
92k
Let's Do A Bunch of Simple Stuff to Make Websites Faster
chriscoyier
501
140k
Side Projects
sachag
451
41k
Git: the NoSQL Database
bkeepers
PRO
421
63k
What the flash - Photography Introduction
edds
64
11k

Transcript

  1. Death to Cookies Konstantin Haase @konstantinhaase

  2. story time

  3. None
  4. None
  5. None

  6. once upon a time

  7. None
  8. None

  9. Recipetastic™

  10. None
  11. None

  12. Bob Alice

  13. Bob Alice

  14. Bob Alice Eve

  15. Bob Alice Mallet

  16. problem solved

  17. None

  18. POST /login HTTP/1.1 Host: www.recipetast.ic Content-Length: 44 [email protected]& password=st0p%20Motion

  19. HTTP/1.1 200 OK Content-Type: text/html Set-Cookie: user=bob <html> ...

  20. GET / HTTP/1.1 Host: www.recipetast.ic Cookie: user=bob

  21. Guessing

  22. None
  23. None
  24. None

  25. HTTP/1.1 200 OK Content-Type: text/html Set-Cookie: user=bob Set-Cookie: pwd=... <html>

    ...

  26. GET / HTTP/1.1 Host: www.recipetast.ic Cookie: user=bob,pwd=...

  27. GET / HTTP/1.1 Host: www.recipetast.ic Cookie: user=bob,pwd=... Basic Auth, just

    with cookies

  28. HTTP/1.1 200 OK Content-Type: text/html Set-Cookie: user=bob Set-Cookie: token=... <html>

    ...
  29. None

  30. XSS Cross Site Scripting

  31. None

  32. can read cookie and send it somewhere

  33. None

  34. HTTP/1.1 200 OK Content-Type: text/html Set-Cookie: user=bob; HttpOnly <html> ...

  35. None

  36. can read (and write) recipes

  37. None

  38. sanitize all user input

  39. Content Security Policy

  40. None

  41. CSRF Cross Site Request Forgery

  42. Is this awesome, y/n?

  43. None

  44. GET /create?… HTTP/1.1 Host: www.recipetast.ic Cookie: user=alice

  45. GET /create?… HTTP/1.1 Host: www.recipetast.ic Cookie: user=alice Deadly cookies!

  46. None

  47. GET, HEAD, OPTIONS, TRACE PUT, DELETE, LINK, UNLINK POST, PATCH

  48. 1 2 PUT / 2 PUT / 2 Repeatable! :)

    State change! :( Deterministic! :) https://speakerdeck.com/rkh/we-dont-know-http

  49. GET, HEAD, OPTIONS, TRACE PUT, DELETE, LINK, UNLINK POST, PATCH

  50. None
  51. None
  52. None

  53. POST /create HTTP/1.1 Host: www.recipetast.ic Cookie: user=alice ...

  54. POST /create HTTP/1.1 Host: www.recipetast.ic Cookie: user=alice ... Deadly cookies!

  55. None

  56. POST /create HTTP/1.1 Host: www.recipetast.ic Referer: http://awesome- website.com/ Cookie: user=alice

  57. POST /create HTTP/1.1 Host: www.recipetast.ic Referer: http://awesome- website.com/ Cookie: user=alice

    [sic]
  58. None
  59. None

  60. Referer is not set for FTP or HTTPS referrers

  61. Referer can be spoofed by outdated flash plugin

  62. None

  63. POST /create HTTP/1.1 Host: www.recipetast.ic Origin: http://awesome- website.com Cookie: user=alice

  64. None
  65. None

  66. Not supported by older browsers

  67. Origin can probably be spoofed by outdated flash plugin

  68. None

  69. HTTP/1.1 200 OK Content-Type: text/html Set-Cookie: csrf_token=XXX

  70. None
  71. None

  72. Cheating Same Origin

  73. HTTP/1.1 200 OK Content-Type: application/json

  74. An attacker could just load it, right?

  75. AJAX can only load from the same origin (or CORS)

  76. None

  77. seems harmless

  78. In JavaScript, you can override the array constructor.

  79. https://github.com/rkh/json-csrf

  80. None

  81. Never serve JSON that has an array at top level

    (or don’t use cookies)
  82. None

  83. VBScript did not fully implement Same Origin

  84. None

  85. Block Internet Explorer before IE9

  86. Block Internet Explorer before IE9

  87. require CSRF token for all AJAX requests

  88. None

  89. Are we doing good so far?

  90. None

  91. Can we trust a cookie?

  92. DNS cache poisoning

  93. Can we trust the browser?

  94. Can we trust browser plugins?

  95. None
  96. None

  97. Signed Cookies

  98. Encrypted Cookies

  99. None

  100. Eaves- dropping

  101. encrypting cookies does not help

  102. None
  103. None
  104. None

  105. attacker cannot parse cookie from stream

  106. None

  107. Or can they?

  108. BEAST Browser Exploit Against SSL/ TLS

  109. decrypts TLS 1.0 streams via injected JavaScript

  110. None

  111. fixed in TLS 1.1

  112. force recent browser

  113. don’t allow TLS 1.0

  114. None

  115. CRIME Compression Ratio Info-leak Made Easy

  116. SSL has built-in compression

  117. GET /?user=alice HTTP/1.1 Host: www.recipetast.ic Cookie: user=bob GET /?user=bob HTTP/1.1

    Host: www.recipetast.ic Cookie: user=bob better compression
  118. None

  119. update your browser

  120. turn off SSL compression

  121. append random number of bytes to response

  122. None

  123. BREACH Browser Reconnaissance and Exfiltration via Adaptive Compression of Hypertext

  124. like CRIME, but for the response

  125. attack the CSRF token, not the cookie

  126. inject something in the response http://www.recipetast.ic/search?q=XXX

  127. None

  128. mask CSRF tokens differently in every response (Rails PR pending)

  129. don’t use CSRF tokens

  130. None

  131. Do you think about all this when you build an

    app?

  132. Next attack vector around the corner?

  133. None

  134. Alternatives

  135. IP address

  136. Session ID in URL

  137. None

  138. Custom Authorization header

  139. None

  140. Store value in Local Storage

  141. Needs JavaScript :(

  142. Works well with PJAX/ Turbo Links like setups

  143. None

  144. New Browser Concepts?

  145. None

  146. @konstantinhaase [email protected] rkh.im