Cookie is used to collect the admin privileges CTF foundation problem

A very basic ctf cookie question, if you don't know much about cookies, you can go here to see
https://blog.csdn.net/playboyanta123/article/details/79464684

Not much to say, go directly to the picture.

Source code is something useless.

According to the meaning of the question, we directly use burp to intercept and change the cookie

If the permission is insufficient after the naked packet capture, we directly change the cookie.
Comparing the u and r in the cookie, it will be found that both start with 351e766803, so let's decrypt (MD5) the following things.

Found that u is username and r is limited.
So we have to change the latter to get admin privileges.
is to change both u and r to 351e766803+md5 (admin), which is 351e76680321232f297a57a5a743894a0e4a801fc3.

Done!flag it appeared!