Description

The application doesn’t check/filter the comments provided by the user before save to database. Attacker can’t insert js code to steal admin’s data but can insert html code, leads to many information security risks.

Proof of Concept

• Step 1: Go to https://demo-publify.herokuapp.com/2022/02/11/hello-world#comments and comment in anonymous user.

<img src="https://www.technistone.com/color-range/image-slab/Starlight%20Black_SLAB_web.jpg" width="2000" height="2000"> 

• Step 2: Login as demo user, go to https://demo-publify.herokuapp.com/admin/feedback. You can see html code has been rendered successfully.
• PoC: https://drive.google.com/file/d/1RSuq7fsyJPrbNHqlZ9pRW3lgXAvmOrQf

Impact

Attacker can insert html code to break the website format, phishing or collect the admin’s IP through loading images in img tags.