[FD] skype installer dll hijacking vulnerability - CVE-2016-5720

[Tien Phan <heart2heart.it@xxxxxxxxx>]

Hi,

There are a dll planting vuln in skype installer. This vuln had been
reported to Microsoft but they decided not fix this.

Here is the vulnerability details:
------
Skype installer in Windows is open to DLL hijacking.

Skype looks for a specific DLL by dynamically going through a set of
predefined directories. One of the directory being scanned is the
installation directory, and this is exactly what is abused in this
vulnerability.

Reproduce Notes:
1. Download this dll
https://mega.nz/#!b4ViSLJL!Pv99pN2d_WxsUHGPH0Ej3onwVeSdh41mpyKfQJfAq8E
2. Copy msi.dll to Downloads directory
3. download skype installer
4. execute the downloaded installer from your "Downloads" directory;
Observed behavior: message box “hyhy”

Another dll can be used to hijack: dpapi.dll cryptui.dll
------

Regards,
Tien



-- 
Tien Phan
Blog : http://tienpp.blogspot.com
twitter : @_razybo_ <http://twitter.com/_razybo_>

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