Magento versions 2.4.2 (and earlier), 2.4.1-p1 (and earlier) and 2.3.6-p1 (and earlier) are vulnerable to an Information Disclosure vulnerability when uploading a modified png file to a product image. Successful exploitation could lead to the disclosure of document root path by an unauthenticated attacker. Access to the admin console is required for successful exploitation.
https://helpx.adobe.com/security/products/magento/apsb21-30.html