Endpoint Security Cross-site Scripting

A stored cross site scripting vulnerability in ePO extension of McAfee Endpoint Security (ENS) prior to 10.7.0 February 2021 Update allows an ENS ePO administrator to add a script to a policy event which will trigger the script to be run through a browser block page when a local non-administrator user triggers the policy. (2021-02-10, CVE-2021-23881)

Cross site scripting vulnerability in the firewall ePO extension of McAfee Endpoint Security (ENS) prior to 10.7.0 November 2020 Update allows administrators to inject arbitrary web script or HTML via the configuration wizard. (2020-11-12, CVE-2020-7333)

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>