When establishing a hotspot on your iPhone, Apple initially sets a seemingly random password to secure it. You can change this password; however, many users just use the provided one. It appears that may be a bad idea.
Three researchers from the German university found that these passwords are generated using a short dictionary word followed by a series of random numbers. In their paper, 'Usability vs. Security: The Everlasting Trade-Off in the Context of Apple iOS Mobile Hotspots (PDF)', they reveal that an attacker can easily determine what passwords iOS uses for its defaults, because there is a limited list of words that are used to generate the password.
"This list consists of around 52,500 entries, and was originated from an open-source Scrabble crossword game. Using this unofﬁcial Scrabble word list within ofﬂine dictionary attacks, we already had a 100 percent success rate of cracking any arbitrary iOS hotspot default password," the researchers wrote.
Even worse, the analysts found that only a few of those 52,500 were being used.
"Only 1,842 different entries of that dictionary are taken into consideration. Consequently, any default password used within an arbitrary iOS mobile hotspot is based on one of these 1,842 different words."
With this information and a cluster of four AMD Radeon HD 7970s, the researchers were able to crack any iOS hotspot with an OS-generated password within 50 seconds.
They note that "system-generated passwords should be reasonably long, and should use a reasonably large character set. Consequently, hotspot passwords should be composed of completely random sequences of letters, numbers, and special characters."
Read More [via Adam]