Apple iOS device users who disable Apple's sandbox security mechanism to have full privileges on iPhones and iPads will have one jailbreak option less after a recent patch relese.
But Apple has now plugged the vulnerability with the release of iOS 9.3.4.
Apple said the vulnerability compromised a memory corruption issue in the IOMobileFrameBuffer kernel extension, which handles the screen framebuffer.
By causing memory corruption, it is possible to run arbitrary code with full kernel privileges on iOS devices.
Team PanGu used the vulnerability to disable Apple's restrictions on what software can be installed on iPhones and iPads, and to enable third-party package managers and app stores such as Cydia.
Such market places may contain cracked, or illicitly distributed software, as well as malware and other malicious apps, and are outside Apple's usual vetting mechanism.