While neither team Pangu or Taig has accepted or denied the fact that they are working on an iOS 9.2.1 jailbreak, a core Pangu team member has come forward to urge iOS users, who are using iOS 9.2 or earlier to upgrade their iPhone, iPad or iPod touch to the latest available version of iOS, i.e iOS 9.2.1. Before you get too excited and think hacker windknown is asking users to upgrade because his team is about to release the much awaited jailbreak, then you would be wrong. The reason why he is recommending users to upgrade in his blog post has nothing to do with the jailbreak, but with security.
He writes as reported by blog Superphen:
It is noteworthy that this loophole in iOS sand box trigger, and therefore in the APP can directly attack the kernel, the kernel code is executed to obtain permission.We recommend that users upgrade to the latest version as soon as possible, and to avoid the installation of unknown origin APP.
As mentioned in the translated text above, the hacker details how a malicious app installed from third-party sources can attack the kernel and execute the kernel code to obtain permissions on an iOS device. To prevent this from happening windknown has asked users to upgrade to latest iOS 9.2.1.
While his blogpost on the official Pangu blog does not suggest that team Pangu is about to release a jailbreak, some have speculated that his recent advisory has to do with the fact that the famous jailbreak team is about to make a big announcement as far as iOS 9 jailbreak is concerned. While we would love that to happen, we would also advice you to manage expectations.
So should you upgrade to iOS 9.2.1? The answer to that question is two fold.
If you are already using iOS 9.2, then you might as well upgrade since whenever a jailbreak is released it will support the latest iOS version at that time. However if you are running an earlier verison of iOS such as iOS 9.0.2 and are jailbroken, then you might want to hold off upgrading and wait for the release of a hack before upgrading. In the end decision is yours to make.