Webaccess Cross-site Scripting

Advantech WebAccess 8.4.2 and 8.4.4 allows XSS via the username column of the bwRoot.asp page of WADashboard. (2021-06-11, CVE-2021-34540)

Unauthenticated reflected cross-site scripting (XSS) exists in Zarafa Webapp 2.0.1.47791 and earlier. NOTE: this is a discontinued product. The issue was fixed in later Zarafa Webapp versions; however, some former Zarafa Webapp customers use the related Kopano product instead. (2019-04-11, CVE-2019-7219)

Advantech WebAccess 8.3.1 and 8.3.2 are vulnerable to cross-site scripting in the Bwmainleft.asp page. An attacker could leverage this vulnerability to disclose credentials amongst other things. (2018-10-31, CVE-2018-15707)

Advantech WebAccess 8.3.2 and below is vulnerable to multiple reflected cross site scripting vulnerabilities. A remote unauthenticated attacker could potentially exploit this vulnerability by tricking a victim to supply malicious HTML or JavaScript code to WebAccess, which is then reflected back to the victim and executed by the web browser. (2018-10-22, CVE-2018-15703)

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>