了解Ruby ERB模板注入，Ruby ERB模板注入检测。

ERB是Ruby自带的

• <% 写逻辑脚本(Ruby语法) %>
• <%= 直接输出变量值或运算结果 %>

require 'erb'

template = "text to be generated: <%= x %>"
erb_object = ERB.new(template)
x = 5
puts erb_object.result(binding())
x = 4
puts erb_object.result(binding())
#Ruby ERB模板注入检测

如果x是可控的，跟普通模板注入一样

require 'erb'

template = "text to be generated: <%= x %>"
erb_object = ERB.new(template)
x = 7*7
puts erb_object.result(binding())

读取一个文件：

require 'erb'

template = "text to be generated: <%= x %>