Security Exploit Can Give Hackers Control of Your iPhone or iPad

clicking a link and loading a PDF file on your idevice is all it takes

[Demaestro]

[mashable.com...]

whenever a user loads a PDF document, it has to load the fonts associated with it. A font can be inserted into the PDF containing a program that will cause a stack overflow. The result is that the program can pass the iPhone’s security defenses and then break out of its protective sandbox

Be cautious about any PDFs you open on your Idevices