Apple has released an update to iOS which fixes various security flaws including one particularly dangerous one affecting Safari on iPhones and iPads. ITS strongly recommends users apply the 5.1.1 update as soon as possible.
The major concern with this particular security advisory is that one of the vulnerabilities listed may allow for “remote code execution”, the security industry’s way of saying “bad things like viruses”. This may open up the iPhone and the iPad to issues similar to those that Mac computers encountered recently with the Flashback virus: what is often called “Drive-by” infection. Drive-by infection is so named because the victim need not fall for any tricks, as is common versus a Trojan horse. Instead, all a victim has to do is visit the wrong place on the web, at the wrong time.
While iPads and iPhones have yet to be a major target for malware, it is this type of hole, combined with the prevalence of the devices, that can lead to an outbreak, and for that reason we strongly recommend upgrading to the latest version.
You can update your device by launching “Settings”, choosing “General”, selecting “Software Update”, and following the on-screen instructions from there.
You can read more about the issue in the following articles: