Dropbox 6.4.14 DLL Hijacking Vulnerability

[mehta.himanshu21 () gmail com]

Aloha,

Summary
Dropbox Installer for Windows contains a DLL hijacking vulnerability that could allow an unauthenticated, remote 
attacker to execute arbitrary code on the targeted system. The vulnerability exists due to some DLL file is loaded by 
'DropboxInstaller.exe' improperly. And it allows an attacker to load this DLL file of the attacker’s choosing that 
could execute arbitrary code without the user's knowledge.

Affected Product: Dropbox 6.4.14 and prior versions

Tested on: Windows 7

Impact
Attacker can exploit this vulnerability to load a DLL file of the attacker's choosing that could execute arbitrary 
code. This may help attacker to Successful exploit the system if user creates shell as a DLL.

Vulnerability Scoring Details
The vulnerability classification has been performed by using the CVSSv2 scoring system (http://www.first.org/cvss/).
Base Score: 7.2 (AV:L/AC:L/Au:N/C:C/I:C/A:C)

More Details:
For software downloaded with a web browser the application directory is typically the user's "Downloads" directory: see 
https://insights.sei.cmu.edu/cert/2008/09/carpet-bombing-and-directory-poisoning.html,
http://blog.acrossecurity.com/2012/02/downloads-folder-binary-planting.html
and http://seclists.org/fulldisclosure/2012/Aug/134 for "prior art" about this well-known and well-documented 
vulnerability.

If an attacker places malicious DLL in the user's "Downloads" directory (for example per "drive-by download" or "social 
engineering") this vulnerability becomes a remote code execution.

Proof of concept/demonstration:

1. Create a malicious PGPmapih.dll file and save it in your "Downloads" directory. 

2. Download 'DropboxInstaller.exe' from https://www.dropbox.com/downloading and save it in your "Downloads" directory. 

3. Execute .exe from your "Downloads" directory. 

4. Malicious dll file gets executed. 

Informed Vendor: Yes
Fixed Version: TBA

Please assign a CVE ID.

Chao!! 
Himanshu Mehta