Apple has released iPhone OS 3.1.3 to provide a couple of performance improvements and address several security threats. Changes include improved accuracy on the iPhone 3GS's battery level display, a fix for a bug that prevented some third party programs from launching, and a fix for an issue that caused application crashes when using the Japanese Kana keyboard.
Also eliminated are three security vulnerabilities that could lead to application crashes and arbitrary code execution after playing maliciously crafted audio files, viewing maliciously crafted TIFF files, or visiting a maliciously configured FTP server. Another fix prevents remote image or video content being loaded in Mail even when remote image loading is turned off. And finally, the update blocks a vulnerability that could enable an attacker with physical access to a locked iPhone or iPod touch to gain control of personal data via the recovery mode. The update is available only via iTunes. (Free, 291 MB)