An indirect object reference (IDOR) vulnerability in the Squiz Matrix web content management system (CMS) could have enabled attackers to seize admin rights on targeted installations.
Squiz Matrix is a browser-based website-building tool reportedly used by more than 280 organizations, including governments, businesses, and half of Australian and New Zealand universities, as well as several UK higher education institutions.
Discovered during a pen-test engagement by Trustwave SpiderLabs, the privilege escalation flaw meant a low privileged user could change the contact details of any user – including administrators.
By changing an administrator’s email to an attacker-controlled address they could then initiate a password reset and take control of their account.
And, “as user account numbers are in a sequential order, an attacker could run through user account numbers and change the details of every user registered to the vulnerable Squiz Matrix instance”, according to a blog post disclosing the flaw.
Squiz Matrix patched the vulnerability for all customers as of June 14, 2022, well before Trustwave disclosed details of the problem on August 31.
Proof of concept
To exploit the bug, an attacker would authenticate to the application as a general level user, navigate to the ‘Edit Contact’ page, and submit the contact-editing form before capturing the request with a web interception proxy.
The resulting request would contain GET and POST parameters named ‘asset_id’ that both contain the targeted user’s user_id.
After changing the asset_id parameter value to a valid user_id, an attacker could then change user details in the POST body, such as changing the email parameter and upgrading userType to sp_admin.
Source: https://portswigger.net/daily-swig/squiz-matrix-cms-squashes-admin-account-takeover-bug
