Bug Bounty Hunter Methodology - Nullcon 2016


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This is a bug bounty hunter presentation given at Nullcon 2016 by Bugcrowd's Faraz Khan.
Learn more about Bugcrowd here: https://bugcrowd.com/join-the-crowd

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Bug Bounty Hunter Methodology - Nullcon 2016

  1. 1. 1 The Bug Hunter’s Methodology
  2. 2. 2 Faraz Khan ● Bugcrowd Tech-OPS Team Member ● Part time Hacker & Bug hunter ● Writer at Securityidiots.com ● Ex-Full time Penetration Tester whoami
  3. 3. 3 These Slides were originally developed and presented by Jason Haddix at Defcon 23 on August 6th ● Director of Technical Ops at Bugcrowd ● Hacker & Bug hunter ● #1 on all-time leaderboard bugcrowd 2014 Source of the Slides @jhaddix
  4. 4. 4 Hack Stuff Better (and practically) What this talk’s about... And…LOTS of memes…. only some of them are funny
  5. 5. 5 Step 1: Started with my bug hunting methodology Step 2: Parsed some of the top bug hunters’ research (web/mobile only for now) Step 3: Create kickass preso Topics? BB philosophy shifts, discovery techniques, mapping methodology, common attack parameters, useful fuzz strings, bypass or filter evasion techniques, new/awesome tooling Note: All information is from Jason Haddix’s own methodology and public resource. No information from the Bugcrowd platform is obtained! More Specifically
  6. 6. 6 Philosophy
  7. 7. 7 Differences from standard testing Single-sourced Crowdsourced ● looking mostly for common-ish vulns ● not competing with others ● incentivized for count ● payment based on sniff test ● looking for vulns that aren’t as easy to find ● racing vs. time ● competitive vs. others ● incentivized to find unique bugs ● payment based on impact not number of findings
  8. 8. 8 Scenario while Standard Penetration Test
  9. 9. 9 Scenario while Bounty Hunting
  10. 10. 10 The regular methodologies
  11. 11. 11 Discovery
  12. 12. 12 Find the road less traveled ^ means find the application (or parts of an application) less tested to avoid duplicate. 1. *.acme.com scope is your friend 2. Find domains via Google (and others!) a. Can be automated well via recon-ng and other tools. 3. Confirm the subdomain to be in Scope 4. Port scan for obscure web servers or services (on all domains) 5. Find acquisitions and the bounty acquisition rules 6. Functionality changes or re-designs 7. Mobile websites 8. New mobile app versions
  13. 13. 13 Tool: Recon-ng script (enumall.sh) https://github.com/jhaddix/domain
  14. 14. 14 LMGTFY
  15. 15. 15 LMGTFY
  16. 16. 16 DEMO: enumall.sh script
  17. 17. 17 LMGTFY Google dorks on Exploit-Db Link: https://www.exploit-db.com/google-hacking-database/
  18. 18. 18
  19. 19. 19 https://www.facebook.com/notes/phwd/facebook-bug-bounties/707217202701640
  20. 20. 20 Port scanning is not just for Netpen! A full port scan of all your new found targets will usually yield #win: ● separate webapps ● extraneous services ● Facebook had Jenkins Script console with no auth ● IIS.net had rdp open vulnerable to MS12_020 nmap -sS -A -PN -p- --script=http-title dontscanme.bro ^ syn scan, OS + service fingerprint, no ping, all ports, http titles Port Scanning!
  21. 21. 21 Mapping
  22. 22. 22 Mapping tips ● Google ● *Smart* Directory Brute Forcing ● RAFT lists (included in Seclists) ● SVN Digger (included in Seclists) ● Git Digger ● Platform Identification: ● Wapplyzer (Chrome) ● Builtwith (Chrome) ● retire.js (cmd-line or Burp) ● Check CVE’s ● Auxiliary ● WPScan ● CMSmap
  23. 23. 23 Just what the hack is SecList? SecLists is the security tester's companion. It's a collection of multiple types of lists used during security assessments, collected in one place. List types include usernames, passwords, URLs, sensitive data patterns, fuzzing payloads, web shells, and many more. The goal is to enable a security tester to pull this repo onto a new testing box and have access to every type of list that may be needed. This project is maintained by Daniel Miessler and Jason Haddix. https://github.com/danielmiessler/SecLists
  24. 24. 24 DEMO: Wapplyzer
  25. 25. 25 DEMO: wpscan
  26. 26. 26 Directory Bruteforce Workflow After bruteforcing look for other status codes indicating you are denied or require auth then append list there to test for misconfigured access control. Example: GET http://www.acme.com - 200 GET http://www.acme.com/backlog/ - 404 GET http://www.acme.com/controlpanel/ - 401 hmm.. ok GET http://www.acme.com/controlpanel/[bruteforce here now]
  27. 27. 27 Auth and Session
  28. 28. 28 Auth (better be quick) Auth Related (more in logic and priv sections) ● Make sure they are in scope before submitting ● User/pass discrepancy flaw ● Registration page harvesting ● Login page harvesting ● Password reset page harvesting ● No account lockout ● Weak password policy ● Password not required for account updates ● Password reset tokens (no expiry or re-use)
  29. 29. 29 Session (better be quick) Session Related ● Failure to invalidate old cookies ● No new cookies on login/logout/timeout ● Never ending cookie length ● Easily reversible cookie (base64 most often)
  30. 30. 30 Tactical Fuzzing - XSS
  31. 31. 31 XSS Core Idea: Does the page functionality display something to the users? For time sensitive testing the 80/20 rule applies. Many testers use Polyglot payloads. You probably have too!
  32. 32. 32 XSS ';alert(String.fromCharCode(88,83,83))//';alert(String. fromCharCode(88,83,83))//";alert(String.fromCharCode (88,83,83))//";alert(String.fromCharCode(88,83,83))//-- ></SCRIPT>">'><SCRIPT>alert(String.fromCharCode(88,83,83)) </SCRIPT> Multi-context, filter bypass based polyglot payload #1 (Rsnake XSS Cheat Sheet)
  33. 33. 33 XSS '">><marquee><img src=x onerror=confirm(1)></marquee>" ></plaintext></|><plaintext/onmouseover=prompt(1) ><script>prompt(1)</script>@gmail.com<isindex formaction=javascript:alert(/XSS/) type=submit>'-->" ></script><script>alert(1)</script>"><img/id="confirm&lpar; 1)"/alt="/"src="/"onerror=eval(id&%23x29;>'"><img src="http: //i.imgur.com/P8mL8.jpg"> Multi-context, filter bypass based polyglot payload #2 (Ashar Javed XSS Research)
  34. 34. 34 XSS “ onclick=alert(1)//<button ‘ onclick=alert(1)//> */ alert(1)// Multi-context polyglot payload (Mathias Karlsson) http://polyglot.innerht.ml/
  35. 35. 35 XSS
  36. 36. 36 Other XSS Observations Input Vectors Customizable Themes & Profiles via CSS Event or meeting names URI based Imported from a 3rd party (think Facebook integration) JSON POST Values (check returning content type) File Upload names Uploaded files (swf, HTML, ++) Custom Error pages fake params - ?realparam=1&foo=bar’+alert(/XSS/)+’ Login and Forgot password forms
  37. 37. 37 SWF Parameter XSS
  38. 38. 38 DEMO: Flashbang
  39. 39. 39 Tactical Fuzzing - SQLi
  40. 40. 40 SQL Injection Core Idea: Does the page look like it might need to call on stored data? There exist some SQLi polyglots, i.e; SLEEP(1) /*‘ or SLEEP(1) or ‘“ or SLEEP(1) or “*/ Works in single quote context, works in double quote context, works in “straight into query” context! (Mathias Karlsson)
  41. 41. 41 SQL Injection You can also leverage the large database of fuzzing lists from Seclists here:
  42. 42. 42 SQL Injection Observations Blind is predominant, Error based is highly unlikely. ‘%2Bbenchmark(3200,SHA1(1))%2B’ ‘+BENCHMARK(40000000,SHA1(1337))+’ SQLMap is king! ● Use -l to parse a Burp log file. ● Use Tamper Scripts for blacklists. ● SQLMapper Burp plugin works well to instrument SQLmap quickly. Lots of injection in web services! Common Parameters or Injection points ID Currency Values Item number values sorting parameters (i.e order, sort, etc) JSON and XML values Cookie values (really?) Custom headers (look for possible integrations with CDN’s or WAF’s) REST based Services
  43. 43. 43 Burp Suite Extension Burp allows you to use a range of addons/extensions which can be added from BAPP Store, you download and add manually or you can program your own script and add to Burp. There are many cool Burp Extensions you can add to your collection to help you automate many manual tasks and make your life easier. Example: - Autorize - CO2 - Reflected Parameters
  44. 44. 44 DEMO: Adding Burp Extension
  45. 45. 45 DEMO: SQLMapper
  46. 46. 46 SQLmap All Tamper Scripts https://forum.bugcrowd.com/t/sqlmap-tamper-scripts-sql-injection-and-waf-bypass/423 --tamper=apostrophemask,apostrophenullencode,appendnullbyte, base64encode,between,bluecoat,chardoubleencode,charencode, charunicodeencode,concat2concatws,equaltolike,greatest, halfversionedmorekeywords,ifnull2ifisnull,modsecurityversioned, modsecurityzeroversioned,multiplespaces,nonrecursivereplacement, percentage,randomcase,randomcomments,securesphere,space2comment, space2dash,space2hash,space2morehash,space2mssqlblank, space2mssqlhash,space2mysqlblank,space2mysqldash,space2plus, space2randomblank,sp_password,unionalltounion,unmagicquotes, versionedkeywords,versionedmorekeywords
  47. 47. 47 SQLmap Targeted Tamper Scripts General: tamper=apostrophemask,apostrophenullencode,base64encode,between,chardoubleencode,charencode, charunicodeencode,equaltolike,greatest,ifnull2ifisnull,multiplespaces,nonrecursivereplacement,percentage, randomcase,securesphere,space2comment,space2plus,space2randomblank,unionalltounion,unmagicquotes MSSQL: tamper=between,charencode,charunicodeencode,equaltolike,greatest,multiplespaces,nonrecursivereplacement, percentage,randomcase,securesphere,sp_password,space2comment,space2dash,space2mssqlblank,space2mysqldash, space2plus,space2randomblank,unionalltounion,unmagicquotes MySQL: tamper=between,bluecoat,charencode,charunicodeencode,concat2concatws,equaltolike,greatest, halfversionedmorekeywords,ifnull2ifisnull,modsecurityversioned,modsecurityzeroversioned,multiplespaces, nonrecursivereplacement,percentage,randomcase,securesphere,space2comment,space2hash,space2morehash, space2mysqldash,space2plus,space2randomblank,unionalltounion,unmagicquotes,versionedkeywords, versionedmorekeywords,xforwardedfor
  48. 48. 48 Best SQL injection resources DBMS Specific Resources mySQL PentestMonkey's mySQL injection cheat sheet Reiners mySQL injection Filter Evasion Cheatsheet MSSQL EvilSQL's Error/Union/Blind MSSQL Cheatsheet PentestMonkey's MSSQL SQLi injection Cheat Sheet ORACLE PentestMonkey's Oracle SQLi Cheatsheet POSTGRESQL PentestMonkey's Postgres SQLi Cheatsheet Others Access SQLi Cheatsheet PentestMonkey's Ingres SQL Injection Cheat Sheet pentestmonkey's DB2 SQL Injection Cheat Sheet pentestmonkey's Informix SQL Injection Cheat Sheet SQLite3 Injection Cheat sheet Ruby on Rails (Active Record) SQL Injection Guide
  49. 49. 49 SSRF - A new face in Picture
  50. 50. 50 SSRF (Server-Side Script Request Forgery) Core Idea : Is there any external resource accessed by any parameter which could be controlled by us. Polyglot : www.yoursite.com/your_resource Simply capture the IP from which your resource is accessed. There we start, once we get the IP and we confirm that the resource is accessed by server- side, we are up with our game for SSRF.
  51. 51. 51 SSRF Tools - Testing & Exploitation Tools Burp Scanner, other few scanners in market…. Testing As we know SSRF does not need automated fuzzing, because once we confirm a resource is accessible from the Server-Side we can confirm SSRF/XFPA. Exploitation Once we have confirmed SSRF, we can move on to further exploitation which includes the following but not limited to: 1. Internal Server/Port Scan 2. Access to File System 3. SSRF via 306 Redirects 4. Exploitation via other known Protocols
  52. 52. 52 DEMO: SSRF
  53. 53. 53 XXE - XML eXternal Entity
  54. 54. 54 XML External Entity Injection Core Idea : Trial & Error, find any XML upload request or any request which takes XML in input body. Not very commonly we finds an application functionality which is dealing with XML inputs. But if we do, we might get lucky to find an XXE. Here’s how it works, if the XML is getting parsed by the application and the External entities in the DTD (Document Type declaration) is resolved then it may lead to XXE. You can also try converting a JSON endpoint request to XML and try XML Injections.
  55. 55. 55 XXE Tools - Testing & Exploitation As the vulnerability is in its early stages we do not have any specific tool that totally concentrate on finding or exploiting XXE, but as per automated scanning/finding we have Burp scanner, other updated automated vulnerability scanner which are able to find XXE. Simple Payload <?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE foo [ <!ELEMENT foo ANY > <!ENTITY xxe SYSTEM "file:///dev/random" >]><foo>&xxe;</foo> Exploitation: Can be used to read system files + Other attacks SSRF is capable of.
  56. 56. 56 DEMO: XXE
  57. 57. 57 Tactical Fuzzing - FI & Uploads
  58. 58. 58 Local file inclusion Core Idea: Does it (or can it) interact with the server file system? Liffy is new and cool here but you can also use Seclists: Common Parameters or Injection points file= location= locale= path= display= load= read= retrieve=
  59. 59. 59 Malicious File Upload ++ File upload attacks are a whole presentation. Try this one to get a feel for bypass techniques: ● content type spoofing ● extension trickery ● File in the hole! presentaion - http://goo.gl/VCXPh6
  60. 60. 60 Malicious File Upload ++ This is an important and common attack vector in this type of testing A file upload functions need a lot of protections to be adequately secure. Attacks: ● Upload unexpected file format to achieve code exec (swf, html, php, php3, aspx, ++) Web shells or... ● Execute XSS via same types of files. Images as well! ● Attack the parser to DoS the site or XSS via storing payloads in metadata or file header ● Bypass security zones and store malware on target site via file polyglots
  61. 61. 61 CSRF
  62. 62. 62 CSRF Everyone knows CSRF but the TLDR here is find sensitive functions and attempt to CSRF. Burps CSRF PoC is fast and easy for this:
  63. 63. 63 CSRF Many sites will have CSRF protection, focus on CSRF bypass! Common bypasses: ● Remove CSRF token from request ● Remove CSRF token parameter value ● Add bad control chars to CSRF parameter value ● Use a second identical CSRF param ● Change POST to GET Check this out...
  64. 64. 64 CSRF Debasish Mandal wrote a python tool to automate finding CSRF bypasses called Burpy. Step 1: Enable logging in Burp. Crawl a site with Burp completely executing all functions. Step 2: Create a template...
  65. 65. 65 DEMO: Burpy
  66. 66. 66 CSRF Or focus on pages without the token in Burp: https://github. com/arvinddoraiswamy/mywebappscripts/blob/master/BurpExtensions/csrf_token_d etect.py
  67. 67. 67 CSRF CSRF Common Critical functions Add / Upload file Password change Email change Transfer Money / Currency Delete File Profile edit CSRF N/A functions Logout CSRF Public Forms Forms that don’t make any change
  68. 68. 68 Privilege, Transport, Logic
  69. 69. 69 Privilege Often logic, priv, auth bugs are blurred. Testing user priv: Here is how it should be: 1. admin has power 2. user has few permissions And we are looking for functions which are only meant for the admin and are accessible by user.
  70. 70. 70 Privilege 1. Find site functionality that is restricted to certain user types 2. Try accessing those functions with lesser/other user roles 3. Try to directly browse to views with sensitive information as a lesser priv user Autorize Burp plugin is pretty neat here... https://github.com/Quitten/Autorize Common Functions or Views Add user function Delete user function start project / campaign / etc function change account info (pass, CC, etc) function customer analytics view payment processing view any view with PII
  71. 71. 71 DEMO: Autorize
  72. 72. 72 Insecure direct object references IDORs are common place in bounties, and hard to catch with scanners. Find any and all UIDs ● increment ● decrement ● negative values ● Attempt to perform sensitive functions substituting another UID ○ change password ○ forgot password ○ admin only functions
  73. 73. 73 Idor’s Common Functions , Views, or Files Everything from the CSRF Table, trying cross account attacks Sub: UIDs, user hashes, or emails Images that are non-public Receipts Private Files (pdfs, ++) Shipping info & Purchase Orders Sending / Deleting messages
  74. 74. 74 Logic Logic flaws that are tricky, mostly manual: ● substituting hashed parameters ● step manipulation ● use negatives in quantities ● authentication bypass ● application level DoS ● Timing attacks
  75. 75. 75
  76. 76. 76 A simple logic Flaw An online cute dog contest, the dog with the best average of likes wins. 1. Anyone can register and take part. 2. Once a dog is registered, people can start liking or disliking that dog. 3. Everyone dislikes each other’s dogs to win the contest 4. The dog with the best average wins the contest. 5. Registration and votings gets closed 5 minutes before the results are announced. What is the Logic Flaw over here?
  77. 77. 77 Auxiliary
  78. 78. 78 The vulns formerly known as “noise” ● Content Spoofing or HTML injection ● Referer leakage ● security headers ● path disclosure ● clickjacking ● ++
  79. 79. 79 Things to take with you… 1. Crowdsourced testing is different enough to pay attention to 2. Crowdsourcing focuses on the 20% because the 80% goes quick 3. Data analysis can yield the most successfully attacked areas 4. A 15 minute web test, done right, could yield a majority of your critical vulns 5. Add polyglots to your toolbelt 6. Use SecLists to power your scanners 7. Remember to periodically refresh your game with the wisdom of other techniques and other approaches Follow these ninjas who I profiled: https://twitter.com/Jhaddix/lists/bninjas
  80. 80. 80 Meme Count: 14
  81. 81. 81 Attribution and Thanks
  82. 82. 82 Tim Tomes - Recon-ng Joe Giron - RFI params Soroush Dalili - File in the Hole preso Mathias Karlsson - polyglot research Ashar Javed - polyglot/xss research Ryan Dewhurst & Wpscan Team Bitquark - for being a ninja, bsqli string rotlogix - liffy LFI scanner Arvind Doraiswamy - HTTPs, CSRF Burp Plugins Barak Tawily - Autorize burp plugin the RAFT list authors Ferruh Mavituna - SVNDigger Jaime Filson aka wick2o - GitDigger Robert Hansen aka rsnake - polyglot / xss Dan Crowley - polyglot research Daniel Miessler - methodology, slide, and data contributions My awesome team at Bugcrowd ( Ashley,Grant,Shpend,Fatih, Dan, Sean,Jay, Patrik ++) Nullcon & All the bug hunting community!!!