This malware is sick: The experimental "Chameleon" malware spreads rapidly among Wi-Fi networks in densely populated areas, much as a disease spreads through crowded urban areas.
Developed in a laboratory at the University of Liverpool in England, Chameleon is the first malware known to propagate by hopping from one Wi-Fi network to another.
MORE: Best Antivirus Software 2014
"It was assumed ... that it wasn't possible to develop a virus that could attack Wi-Fi networks; but we demonstrated that this is possible and that it can spread quickly," Alan Marshall, Professor of Network Security, said in a statement.
Chameleon is technically a worm, not a virus, because it replicates without human assistance by trying to crack the password of each new Wi-Fi router it encounters. Chameleon nevertheless behaves like a biological infectious organism, jumping among overlapping Wi-Fi networks as an airborne disease spreads among humans.
The researchers simulated Chameleon infections in London and Belfast and found that just a few infected devices can spread the worm to "thousands of infected devices within 24 hours."
Furthermore, because Chameleon doesn't migrate beyond Wi-Fi routers, it is undetectable to current anti-virus software, which scans for threats on computers and the Internet.
In its current state, Chameleon doesn't do much more than replicate itself and identify poorly protected Wi-Fi networks, but the researchers say in their paper that such malware could be used to eavesdrop on Internet traffic, alter or destroy data packets or destroy an infected Wi-Fi router.
Chameleon doesn't exist in the wild, so there's no real risk of infection. The good news is a strong Wi-Fi password will keep your router safe from this kind of malware; if it can't break into your router, it will simply move on to the next available one.
The bad news is that many commercial and private Wi-Fi networks have weak passwords, or simply aren't password-protected at all.
In that sense, a Wi-Fi password is like a vaccine; having it will protect not only you, but the people (or Wi-Fi routers) around you as well.
Email email@example.com or follow her @JillScharr and Google+. Follow us @TomsGuide, on Facebook and on Google+.
- 13 Security and Privacy Tips for the Truly Paranoid
- 'War Biking' San Francisco Reveals Lousy Wi-Fi Security
- 7 Ways to Lock Down Your Online Privacy