There were two malicious dumps submitted to /r/VitaPiracy on reddit recently that can permanently brick Vita. It basically remounts os0 and vs0 as read/write and then wipes out their contents which contains Vita's OS. The two malicious dumps are "Fruit Ninja [US] [TESTED] [MAIDUMP]" and "kung fu rabbit - tested working - maidump v233.2z8".
/r/VitaPiracy has issued a warning here: https://www.reddit.com/r/VitaPiracy/comments/55farx/community_warning_there_have_been_two_separate/
Reddit user "realshotgun" provided a simple way to check new dumps for suspicious behavior for the time being:
There have been two dumps posted that will perma brick vitas, they were malicious and not a result of a bad dump with mai, the culprit is the mai.suprx in the two that were posted, but could feasibly be any of the executable files. To be safe, check all bin, self and suprx files for things related to os0.
You can check for it by opening the file in a text or hex editor and searching (ctrl+f) for os0, if it finds anything DO NOT INSTALL IT, YOU WILL PERMA BRICK YOUR SHIT.
At some point in the next day or so, there should be a tool which will make the eboots run within the vita sandbox, which should mitigate the risks, please use this tool on your dumps before installing them.
This is essentially the first Vita malware and will for sure evolve in the future to make detection even harder, such as encrypting the malicious payload. All Henkaku users should be aware and get homebrew & game dumps from reliable sources.