If you have a jailbroken iOS device or want to jailbreak your it, you should hold off on updating to the new Software iOS 9.1, because Apple blocks Pangu on iOS 9.1. Apple has patched the vulnerabilities on iOS 9, which was used to jailbreak the iOS. The latest jailbreak tool -Pangu can only be used for iOS 9.0 – 9.0.2. From the explanation of Apple’s document on the security content of iOS 9.1, Pangu team has found 2 vulnerabilities that have been patched.

Configd:

• Available for: iPhone 4s and later, iPod touch (5th generation) and later, iPad 2 and later
• Impact: A malicious application may be able to elevate privileges
• Description: A heap based buffer overflow issue existed in the DNS client library. A malicious application with the ability to spoof responses from the local configd service may have been able to cause arbitrary code execution in DNS clients.
• CVE-2015-7015 : PanguTeam

GasGauge:

• Available for: iPhone 4s and later, iPod touch (5th generation) and later, iPad 2 and later
• Impact: A malicious application may be able to execute arbitrary code with kernel privileges
• Description: A memory corruption issue existed in the kernel. This issue was addressed through improved memory handling.
• CVE-2015-6979 : PanguTeam

If you have updated your iOS device to iOS 9.1, you are still able to downgrade. Apple is still opening the signing window for 9.0.2 for one week ahead.

Source: iClarified

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