------------------------------------------------------------------------ Shockwave Flash Object DLL side loading vulnerability ------------------------------------------------------------------------ Yorick Koster, August 2015 ------------------------------------------------------------------------ Abstract ------------------------------------------------------------------------ A DLL side loading vulnerability was found in the Flash version that ships with Windows. This issue can be exploited by loading the Shockwave Flash object as an embedded OLE object. When instantiating the object Windows will try to load the DLL spframe.dll from the current working directory. If an attacker convinces the user to open a specially crafted (Office) document from a directory also containing the attacker's DLL file, it is possible to execute arbitrary code with the privileges of the target user. This can potentially result in the attacker taking complete control of the affected system. ------------------------------------------------------------------------ See also ------------------------------------------------------------------------ https://advisory.securify.nl/blog/SFY20151201/there_s_a_party_in_ole__and_you_are_invited.html ------------------------------------------------------------------------ Tested versions ------------------------------------------------------------------------ This issue was successfully verified on Windows 10 + Office 2013 32-bit. ------------------------------------------------------------------------ Fix ------------------------------------------------------------------------ It appears that this issue has been resolved by the security updates for Adobe Flash Player of November 2015 (version 19.0.0.245 or later, APSB15-28 [3]). The initialization code has been changed in this version. Currently, the DLL spframe.dll is only loaded if Flash is started from Microsoft Edge. In all other cases, Flash tries to load ieframe.dll instead of spframe.dll. ieframe.dll is located in System32, which is searched before the current working directory, preventing side loading of this DLL. ------------------------------------------------------------------------ Details ------------------------------------------------------------------------ https://www.securify.nl/advisory/SFY20150802/shockwave_flash_object_dll_side_loading_vulnerability.html