4images Cross-site Scripting

A cross-site scripting (XSS) vulnerability in the admin login panel in 4images version 1.8 allows remote attackers to inject JavaScript via the "redirect" parameter. (2021-03-22, CVE-2021-27308)

4images Image Gallery Management System 1.7.11 is affected by cross-site scripting (XSS) in the Image URL. This vulnerability can result in an attacker to inject the XSS payload into the IMAGE URL. Each time a user visits that URL, the XSS triggers and the attacker can be able to steal the cookie according to the crafted payload. (2021-01-26, CVE-2020-35853)

Cross site scripting is an attack where a web page executes code that is injected by an adversary. It usually appears, when users input is presented. This attack can be used to impersonate a user, take over control of the session, or even steal API keys.

The attack can be executed e.g. when you application injects the request parameter directly into the HTML code of the page returned to the user:

https://server.com/confirmation?message=Transaction+Complete

what results in:

<span>Confirmation: Transaction Complete</span>

In that case the message can be modified to become a valid Javascript code, e.g.:

https://server.com/confirmation?message=<script>dangerous javascript code here</script>

and it will be executed locally by the user's browser with full access to the user's personal application/browser data:

<span>Confirmation: <script>dangerous javascript code here</script></span>