Talos Vulnerability Report

TALOS-2016-0232

Moxa AWK-3131A Web Application Cross-Site Request Forgery Vulnerability

April 10, 2017

Report ID

CVE-2016-8718

Summary

An exploitable Cross-Site Request Forgery vulnerability exists in the Web Application functionality of Moxa AWK-3131A Wireless Access Point running firmware 1.1. A specially crafted form can trick a client into making an unintentional request to the web server which will be treated as an authentic request.

Tested Versions

Moxa AWK-3131A Series Industrial IEEE 802.11a/b/g/n wireless AP/bridge/client 1.1

Product URLs

http://www.moxa.com/product/AWK-3131A.htm

CVSSv3 Score

7.5 - CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

An exploitable Cross-Site Request Forgery (CSRF) vulnerability exists in the Web Application functionality of Moxa AWK-3131A Series Industrial IEEE 802.11a/b/g/n wireless AP/bridge/client. A specially crafted form can trick a client into making an unintentional request to the web server which will be treated as an authentic request.

Successful exploitation of this vulnerability can enable an attacker to trick a legitimate user in to performing any action permitted by the device, including exploitation of unrelated vulnerabilities. For example, an attacker may use a CSRF attack to modify device settings or even take advantage of OS Command Injection vulnerabilities to execute operating system commands with root privileges.

Exploit Proof-of-Concept

The below will change the user’s password to a value determined by the attacker <html> <body> <form action="http://<device IP>/forms/webSetUserChgPwd" method="POST"> </form> </body> </html>

Alternatively, leveraging an OS Command Injection vulnerability in conjunction with CSRF, a client which attempts to render the below page will cause a root-level shell to be opened on the vulnerable device: <html>
<body> <form action="http://<device IP>/forms/webSetPingTrace" method="POST"> </form>

<script>
  		document.forms[0].submit();
	</script>
  		</body>
</html>

Mitigation

To significantly mitigate risk of exploitation, disable the web application before the device is deployed.

Credit

Discovered by Patrick DeSantis of Cisco Talos.

Timeline

2016-11-14 - Vendor Disclosure
2017-04-10 - Public Release