Security Advisory for Contao

24. October 2023

The usd HeroLab analysts examined the Contao content management system while conducting their security analysis. It is an open source software that enables the creation of professional websites and scalable web applications.

While conducting the security analysis a cross-site scripting (XSS) vulnerability was identified. Attackers with a low-privileged role were able to use a modified HTTP request to create an article with a JavaScript payload of their choice, which was client-triggered on the frontend and backend. For example, such an attack could elevate a low-privileged account to an administrator account.

The vulnerability was reported to the vendor under the Responsible Disclosure Policy and subsequently fixed. Detailed information about the advisory can be found here.

About usd HeroLab Security Advisories

In order to protect businesses against hackers and criminals, we must ensure that our skills and knowledge are up to date at all times. Therefore, security research is just as important to our work as is building up a security community to promote an exchange of knowledge. After all, more security can only be achieved if many people take on the task.

We analyze attack scenarios, which are changing constantly, and publish a series of Security Advisories on current vulnerabilities and security issues – always in line with our Responsible Disclosure Policy.

Always in the name of our mission: “more security.”

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