139 email graphic Verification Code bypass (currently, predictable use cases of graphic verification codes)

Graph testing is often used to protect key functions and prevent automated attacks. 139 email graphic verification can be easily bypassed without protection
139 email image verification is applied in multiple places, all of which are the same set of image verification. For example, you can use a simple method to bypass graph verification on the above registration page. If you do not need to view the image verification content, enter 1.2.3.4 or any one of the letters a, B, c, and d, take c as an example. If you submit the job after the first input, a graphic verification error is displayed, indicating that the packet capture result is displayed, as shown in. If an error occurs, the job is submitted with a fixed value c regardless of the error message, when the number of packets is large, it can be successful only several times. When the next page is displayed, the packet capture success message is displayed.


Similarly, you can use the same method to bypass graph verification in other places. Most of them only need to send a request several times to manually prove, can be directly in the http://mail.10086.cn/webmail/reg/index.html input c, or number 2 or 3 or something, don't worry about the error prompt repeated submit fixed value, just a few times to bypassSolution:

You are more professional, and I will not talk much about the solution.