A new iPhone security update should be available on Saturday, claims a spokesperson for the device's UK carrier, O2. "We will be communicating to customers both through the website and proactively," the spokesperson says. Apple has not announced or previewed any iPhone firmware update beyond the major iPhone 3.1 release.

The company could be willing to post an intermediary update, however, to counter an SMS vulnerability exposed at this week's Black Hat security conference. By sending out modified text messages, presenters noted, it should be possible to disable or control a distant iPhone, all without alerting a user to a hacker's presence. The vulnerability exists not just on the iPhone, but also on devices running Android or Windows Mobile.

Fixes are said to be possible either through an operating system update, or else active message scanning on the part of a carrier. O2 suggests that Apple has gone the former route, while the BBC reports that Google has already produced an Android fix. No Apple statement has been offered on the issue.