ZKTeco ZKTime.Net 3.0.1.6 Insecure File Permissions

### Summary ZKTime.Net V3.0 is a new generation time attendance management software. Meanwhile, it integrates with time attendance and access control system. Some frequently used functions such as attendance reports, device management and employee management can be managed directly on the home page which providing excellent user experience. Owing to the Pay code function, it can generate both time attendance records and corresponding payroll in the software and easy to merge with the most ERP and Payroll software, which can rapidly upgrade your working efficiency. The brand new flat GUI design and humanized structure will make your daily management more pleasant and convenient. ### Description ZKTime.Net suffers from an elevation of privileges vulnerability which can be used by a simple 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 'Everyone' group, making the entire directory 'ZKTimeNet3.0' and its files and sub-dirs world-writable. ### Vendor ZKTeco Inc. - http://www.zkteco.com ### Affected Version * 3.0.1.6 * 3.0.1.5 (160622) * 3.0.1.1 (160216) ### Tested On * Microsoft Windows 7 Ultimate SP1 (EN) * Microsoft Windows 7 Professional SP1 (EN) ### PoC ``` C:\>showacls "c:\Program Files (x86)\ZKTimeNet3.0" c:\Program Files (x86)\ZKTimeNet3.0 Everyone Change [RWXD] NT SERVICE\TrustedInstaller Special Access [A] NT AUTHORITY\SYSTEM Special Access [A] BUILTIN\Administrators Special Access [A] BUILTIN\Users Special Access [RX] CREATOR OWNER Special Access [A] C:\>showacls "c:\Program Files (x86)\ZKTimeNet3.0\ZKTimeNet.exe" c:\Program Files (x86)\ZKTimeNet3.0\ZKTimeNet.exe Everyone Change [RWXD] C:\Program Files (x86)>cacls ZKTimeNet3.0 C:\Program Files (x86)\ZKTimeNet3.0 Everyone:(OI)(CI)C NT SERVICE\TrustedInstaller:(ID)F NT SERVICE\TrustedInstaller:(CI)(IO)(ID)F NT AUTHORITY\SYSTEM:(ID)F NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Administrators:(OI)(CI)(IO)(ID)F BUILTIN\Users:(ID)R BUILTIN\Users:(OI)(CI)(IO)(ID)(special access:) GENERIC_READ GENERIC_EXECUTE CREATOR OWNER:(OI)(CI)(IO)(ID)F C:\Program Files (x86)\ZKTimeNet3.0>cacls *.exe C:\Program Files (x86)\ZKTimeNet3.0\LanguageTranslate.exe Everyone:C Everyone:(ID)C NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Users:(ID)R C:\Program Files (x86)\ZKTimeNet3.0\unins000.exe Everyone:(ID)C NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Users:(ID)R C:\Program Files (x86)\ZKTimeNet3.0\ZKTimeNet.DBTT.exe Everyone:C Everyone:(ID)C NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Users:(ID)R C:\Program Files (x86)\ZKTimeNet3.0\ZKTimeNet.exe Everyone:C Everyone:(ID)C NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Users:(ID)R C:\Program Files (x86)\ZKTimeNet3.0\ZKTimeNet.Update.exe Everyone:C Everyone:(ID)C NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Users:(ID)R C:\Program Files (x86)\ZKTimeNet3.0\ZKTimeNet.ZKTime5DB.exe Everyone:C Everyone:(ID)C NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Users:(ID)R ```