Cisco’s Collective Security Intelligence ecosystem Talos has issued a release notifying Apple device users of a security risk.

A hacker could potentially create malware saved as a TIFF image file. Once the TIFF file is sent using using iMessage, the image is rendered automatically using default settings. This could cause the malware to execute without user intervention.

This applies to Apple devices with versions of iOS prior to version 9.3.3, and for OS X versions prior to El Capitan 10.11.6.

Instructions on how to update iPhones and other Apple devices can be found at: https://support.apple.com/en-us/HT204204