f.lux DLL Hijacking
Posted on 15 July 2016
Aloha, f.lux suffers from a DLL hijacking vulnerability. "flux-setup.exe" loads and executes dll from its "application directory". For software downloaded with a web browser the applicationdirectory 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 dll file and save it in your "Downloads" directory. 2. Download "flux-setup.exe" from https://justgetflux.com/ and save it in your "Downloads" directory. 3. Execute "flux-setup.exe" from your "Downloads" directory. 4. Malicious dll file gets executed. Fixes will be available in next build. Chao!! Himanshu Mehta
