Document Title:  
VisualWare MyConnection Server 11.x Remote Code Execution Vulnerability  
References (Source):  
Release Date:  
Product & Service Introduction:  
MCS tests, measures & reports the performance and health of any network  
connection, LAN or WAN. MCS is an access everywhere web based enterprise  
Vulnerability Information:  
Class: CWE-434: Unrestricted Upload of File with Dangerous Type  
Impact: Remote Code Execution  
Remotely Exploitable: Yes  
Locally Exploitable: Yes  
CVE Name: CVE-2021-27198  
Vulnerability Description:  
An unauthenticated remote code execution vulnerability was discovered in  
Visualware MyConnection Server 11.0 through 11.0b build 5382. The web  
endpoint at "" provides an unauthenticated  
user the ability to upload an arbitrary file to an arbitrary location via a  
specially crafted POST request. This application is written in Java and is  
thus cross-platform. The Windows installation executes the web server as  
SYSTEM which means that exploitation provides Administrator privileges on  
the target system.  
Vulnerability Disclosure Timeline:  
2021-01-11: Contacted VisualWare About Issue via Website Contact Form  
2021-02-03: Emailed Multiple VisualWare POCs Requesting Disclosure  
2021-02-11: Requested CVE from MITRE for vulnerability  
2021-02-12: Messaged Lead VisualWare Developer on LinkedIn After Seeing They  
Had Looked At My Profile. I assume because of my attempts to contact them  
2021-02-18: Notified VisualWare About Issue Again via Website Contact Form  
And Notified Them I Would be Disclosing if they did not respond  
2021-02-25: Publicly releasing vulnerability because company refuses to  
respond to any attempts to coordinate disclsoure  
Affected Product(s):  
VisualWare MyConnection Server 11.0 through 11.0b build 5382  
Severity Level:  
Proof of Concept (PoC):  
A proof of concept will not be provided at this time.  
Solution - Fix & Patch:  
Security Risk:  
The security risk of this remote code execution vulnerability is estimated  
as high. (CVSS 10.0)  
Credits & Authors:  
Securifera, Inc - b0yd (@rwincey)  
Disclaimer & Information:  
The information provided in this advisory is provided as it is without any  
warranty. Securifera disclaims all   
warranties, either expressed or implied,   
including the warranties of merchantability and capability for a particular  
purpose. Securifera is not liable in any   
case of damage,   
including direct, indirect, incidental, consequential loss of business  
profits or special damages, even if Securifera   
or its suppliers have been advised   
of the possibility of such damages. Some states do not allow the exclusion  
or limitation of liability for consequential   
or incidental damages so the foregoing   
limitation may not apply. We do not approve or encourage anybody to break  
any licenses, policies, or hack into any   
Contact: contact [at] securifera [dot] com  
Copyright C 2021 | Securifera, Inc