According to a recent tweet from @comex, ion1c exploit may still exist in iOS 4.3.2 (as far as he could see). It has always been an Apple trend to fix the exploit in every other firmware release and some of them have been released considering only the hacker point of view. It was earlier depicted that Apple might close the loophole in the exploit after the release of iOS 4.3.1 untethered JB. @iH8sn0w also suggested that a very important component has been compiled on 3 April, 2011 in iOS 4.3.2 firmware which could still make it vulnerable.
It has been confirmed by @MuscleNerd that the current version of Redsn0w is capable of JailBreaking iOS 4.3.2 but it would be a tethered JailBreak (you need a software every-time you reboot the device). This doesn’t indicate that the untethered ion1c exploit has been closed. However, there is no official word from the @MuscleNerd or DevTeam that the exploit still persists on the latest software update or not.
We will keep  you updated about the latest information on it. Stay tuned!
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