ShoprLynx 9.2.3 Insecure File Permissions

ShaprLynx v9.2.3 Insecure File Permissions


Vendor: Lynx Software Pty Ltd.
Product web page: https://www.sharplynx.com
Affected version: 9.02.0003

Summary: B
ShaprLynx v9.2.3 Insecure File Permissions


Vendor: Lynx Software Pty Ltd.
Product web page: https://www.sharplynx.com
Affected version: 9.02.0003

Summary: Back Office Software for Sharp POS Terminals. Catering for
the needs of retail and hospitality businesses, SharpLynx has been
developed as a modular software solution with options from simple
program management and sales analysis through to multi-location stock
control.

Desc: SharpLynx suffers from an elevation of privileges vulnerability
which can be used by a simple authenticated user that can change the
executable file with a binary of choice. The vulnerability exist due
to the improper permissions, with the 'C' flag (Change) for 'Authenticated
Users' group.

Tested on: Microsoft Windows 7 Professional SP1 (EN)


Vulnerability discovered by Gjoko 'LiquidWorm' Krstic
@zeroscience


Advisory ID: ZSL-2018-5456
Advisory URL: https://www.zeroscience.mk/en/vulnerabilities/ZSL-2018-5456.php


27.03.2018

--


C:>cacls "Lynx Software"
C:Lynx Software BUILTINAdministrators:(ID)F
BUILTINAdministrators:(OI)(CI)(IO)(ID)F
NT AUTHORITYSYSTEM:(ID)F
NT AUTHORITYSYSTEM:(OI)(CI)(IO)(ID)F
BUILTINUsers:(OI)(CI)(ID)R
NT AUTHORITYAuthenticated Users:(ID)C
NT AUTHORITYAuthenticated Users:(OI)(CI)(IO)(ID)C


C:Lynx SoftwareSharpLynx v9>dir *.exe
Volume in drive C has no label.
Volume Serial Number is 54D3-A5E6

Directory of C:Lynx SoftwareSharpLynx v9

02/22/2018 02:23 PM 527,840 SL.exe
02/22/2018 02:23 PM 6,747,104 SLE.exe
02/22/2018 02:23 PM 6,747,104 SLED.exe
02/22/2018 02:23 PM 6,747,104 SLER.exe
02/22/2018 02:23 PM 4,932,064 SLU.exe
02/22/2018 02:23 PM 4,932,064 SLUR.exe
07/15/2016 05:58 PM 7,590,288 TeamViewerQS_en.exe
7 File(s) 38,223,568 bytes
0 Dir(s) 2,677,899,264 bytes free

C:Lynx SoftwareSharpLynx v9>cacls *.exe
C:Lynx SoftwareSharpLynx v9SL.exe BUILTINAdministrators:(ID)F
NT AUTHORITYSYSTEM:(ID)F
BUILTINUsers:(ID)R
NT AUTHORITYAuthenticated Users:(ID)C

C:Lynx SoftwareSharpLynx v9SLE.exe BUILTINAdministrators:(ID)F
NT AUTHORITYSYSTEM:(ID)F
BUILTINUsers:(ID)R
NT AUTHORITYAuthenticated Users:(ID)C

C:Lynx SoftwareSharpLynx v9SLED.exe BUILTINAdministrators:(ID)F
NT AUTHORITYSYSTEM:(ID)F
BUILTINUsers:(ID)R
NT AUTHORITYAuthenticated Users:(ID)C

C:Lynx SoftwareSharpLynx v9SLER.exe BUILTINAdministrators:(ID)F
NT AUTHORITYSYSTEM:(ID)F
BUILTINUsers:(ID)R
NT AUTHORITYAuthenticated Users:(ID)C

C:Lynx SoftwareSharpLynx v9SLU.exe BUILTINAdministrators:(ID)F
NT AUTHORITYSYSTEM:(ID)F
BUILTINUsers:(ID)R
NT AUTHORITYAuthenticated Users:(ID)C

C:Lynx SoftwareSharpLynx v9SLUR.exe BUILTINAdministrators:(ID)F
NT AUTHORITYSYSTEM:(ID)F
BUILTINUsers:(ID)R
NT AUTHORITYAuthenticated Users:(ID)C

C:Lynx SoftwareSharpLynx v9TeamViewerQS_en.exe BUILTINAdministrators:(ID)F
NT AUTHORITYSYSTEM:(ID)F
BUILTINUsers:(ID)R
NT AUTHORITYAuthenticated Use
rs:(ID)C


C:Lynx SoftwareSharpLynx v9>icacls SLE.exe
SLE.exe BUILTINAdministrators:(I)(F)
NT AUTHORITYSYSTEM:(I)(F)
BUILTINUsers:(I)(RX)
NT AUTHORITYAuthenticated Users:(I)(M)

Successfully processed 1 files; Failed processing 0 files