http://blog.metasploit.com/2010/08/expl ... flaws.html
and
https://www.microsoft.com/technet/secur ... 69637.mspx

and various others such as :

http://secunia.com/advisories/41197/

We have run all the suggested tests on both build 2.0050 and 2.0054 (the current latest release) of the PDF-XChange Viewer and concluded that whilst the initial tests suggest a potential flaw is possible - once the full tests are run - the results come back that the PDF-XChange Viewer is in fact not affected - on either build detailed.

After further exhaustive testing - we do accept however that there is still some (almost inconceivably small) potential 'latitude' for an exploit to occur and we will be adding additional security code to fully block any potential for substitute dll's to be used from any location other than the required genuine DLL's.

This build will be available (2.00.55) during the week beginning September 6th 2010 as part of our scheduled product update offering.

UPDATE - 13th September, 2010.
We have now releaseed build 2.055 and have included code to block any possibilty of the above occuring !
All existing users are advised to update from our downloads page or use the option in the Viewer itself : Help -> Check for Updates.