St. Pölten UAS  
title| Multiple XSS in Advantech  
product| Advantech EKI-1524-CE series, EKI-1522 series,  
| EKI-1521 series  
vulnerable version| <=1.21 (CVE-2023-4202), <=1.24 (CVE-2023-4203)  
fixed version| 1.26  
CVE number| CVE-2023-4202, CVE-2023-4203  
impact| Medium  
found| 2023-05-04  
by| R. Haas, A. Resanovic, T. Etzenberger, M. Bineder  
| This vulnerability was discovery during research at  
| St. Pölten UAS, supported and coordinated by CyberDanube.  
| |  
Vendor description  
“Advantech’s corporate vision is to enable an intelligent planet. The company  
is a global leader in the fields of IoT intelligent systems and embedded  
platforms. To embrace the trends of IoT, big data, and artificial intelligence,  
Advantech promotes IoT hardware and software solutions with the Edge  
Intelligence WISE-PaaS core to assist business partners and clients in  
connecting their industrial chains. Advantech is also working with business  
partners to co-create business ecosystems that accelerate the goal of  
industrial intelligence.”  
Vulnerable versions  
EKI-1524-CE series / 1.21 (CVE-2023-4202)  
EKI-1522-CE series / 1.21 (CVE-2023-4202)  
EKI-1521-CE series / 1.21 (CVE-2023-4202)  
EKI-1524-CE series / 1.24 (CVE-2023-4203)  
EKI-1522-CE series / 1.24 (CVE-2023-4203)  
EKI-1521-CE series / 1.24 (CVE-2023-4203)  
Vulnerability overview  
1) Stored Cross-Site Scripting (XSS) (CVE-2023-4202, CVE-2023-4203)  
Two stored cross-site scripting vulnerabilities has been identified in the  
firmware of the device. The first XSS was identified in the "Device Name" field  
and the second XSS was found in the "Ping" tool. This can be exploited in the  
context of a victim's session.  
Proof of Concept  
1) Stored Cross-Site Scripting (XSS)  
Both cross-site scripting vulnerabilities are permanently affecting the device.  
1.1) Stored XSS in Device Name CVE-2023-4202  
The first vulnerability can be triggerd by setting the device name  
("System->Device Name") to the following value:  
This code prints out the cached cookies to the screen.  
1.2) Stored XSS in Ping Function CVE-2023-4203  
The second XSS vulnerability can be found in "Tools->Ping". The following GET  
request prints the current cached cookies of a user's session to the screen.  
An alternative to the used payload is using "onmouseover" event tags. In this  
case it prints out the number "1337":  
" onmousemove="alert(1337)"  
The vulnerability was manually verified on an emulated device by using the  
MEDUSA scalable firmware runtime (  
Upgrade to the newest available firmware.  
Advantech customers are advised to upgrade the firware to the latest  
available version.  
Contact Timeline  
2023-05-16: Contacting vendor via security contact.  
2023-05-24: Contact stated that issue 1.1) is solved after firmware v1.21.  
The contact is trying to reproduce issue 1.2; Gave advice to  
reproduce issue.  
2023-05-25: Contact stated that new firmware should resolve the issue.  
2023-06-03: Sent new payload to the vendor.  
2023-06-05: Vendor asked for clarification; Sent further explaination to the  
contact; Vendor contact said he knows a solution.  
2023-06-22: Asked for an update; Contact stated that the beta firmware should  
resolve the issues.  
2023-06-27: Asked for the release date.  
2023-07-04: Contact stated, that they are currently doing QA tests.  
2023-07-06: Asked if issue 1.1 is really resolved to be released; Vendor stated  
that it can be published.  
2023-07-17: Assigned CVE numbers for the issues. Asked for an update.  
2023-07-18: Vendor contact stated that the firmware will be released end of  
2023-08-07: Asked contact for the new firmware version.  
2023-08-08: Received version 1.26 as the official released firmware with fixes.  
Coordinated release of security advisory.  
Mail: mis at fhstp dot ac dot at  
EOF T. Weber / @2023