iOS 6.1.3 is out, providing "improvements and bug fixes" in Apple's usual terse terms.

The only improvement called out by the company concerns Maps in Japan, but multiple security fixes have been revealed.

The headline fix from Apple's perspective is one that blocks a widely-publicised technique to bypass the lock screen and access the Phone app.

Other security issues addressed concern flaws in the handling of USB drivers and of SVG files in web pages, both of which could previously be exploited to execute arbitrary code.

The update includes patches for three flaws used in the Evasi0n jailbreak - dyld previously allowed the execution of unsigned code in certain circumstances, the iOS kernel could be tricked into revealing its structures, and Lockdown could be tricked into changing permissions on certain files by using symlinks.

Updating an iPhone 5 to iOS 6.1.3 undoes the effect of Evasi0n and prevents the jailbreak from being reapplied. The Redsn0w tethered jailbreak reportedly still works with A4-based iOS devices.

The Apple TV software has also been updated with the fixes for the three Evasi0n bugs.