How your smartphone's battery life can be used to invade your privacy

The Guardian ^ | Tuesday 4 August 2015 | Alex Hern

[TigerLikesRooster]

How your smartphone's battery life can be used to invade your privacy

A group of researchers have demonstrated how to track users with nothing more than their remaining battery power, which could compromise privacy

Alex Hern

Tuesday 4 August 2015 08.18 BST

A little-known feature of the HTML5 specification means that websites can find out how much battery power a visitor has left on their laptop or smartphone – and now, security researchers have warned that that information can be used to track browsers online.

The battery status API is currently supported in the Firefox, Opera and Chrome browsers, and was introduced by the World Wide Web Consortium (W3C, the organisation that oversees the development of the web’s standards) in 2012, with the aim of helping websites conserve users’ energy. Ideally, a website or web-app can notice when the visitor has little battery power left, and switch to a low-power mode by disabling extraneous features to eke out the most usage.

W3C’s specification explicitly frees sites from needing to ask user permission to discover they remaining battery life, arguing that “the information disclosed has minimal impact on privacy or fingerprinting, and therefore is exposed without permission grants”. But in a new paper from four French and Belgian security researchers, that assertion is questioned.

[null and void]

A string and two tin cans sounds better every day. *sigh*

[null and void]

At no point in history has any government ever wanted its people to be defenseless for any good reason ~ nully's son

The biggest killer of mankind

Nut-job Conspiracy Theory Ping!

To get onto The Nut-job Conspiracy Theory Ping List you must threaten to report me to the Mods if I don't add you to the list...

[Ray76]

Another factor in browser fingerprinting

https://panopticlick.eff.org/

[sickoflibs]

Windows tells websites our laptops battery info?

This sounds strange.

I never use my laptop PCs on battery power anyway(or very rarely), its always charging.

[TigerLikesRooster]

Hmm... so many ways to track. Thanks for the info.

[TigerLikesRooster]

I never use my laptop PCs on battery power anyway(or very rarely), its always charging.

My guess is that they will check anyway. How else would they know if your battery is full?

[BitWielder1]

Battery full = You're home and plugged in.
Battery less than 100% = You're roaming about and possibly up to no good.

[bigbob]

I don’t care, they will be pretty bored.

[TigerLikesRooster]

The best cover for secret agents are men leading a boring life. You are not off the hook.:-)

[FreedomOfExpression]

It's not Windows, it's the Internet browser you use.
Firefox, Opera, and Chrome browsers are specifically mentioned in the excerpt.
These browsers are available for Android and Apple devices as well as Windows.

[JoeProBono]

[sickoflibs]

Thanks, I am no expert at this but doesn’t windows and antivirus SW control what computer system info gets sent back across the internet by a browser?

What about privacy mode?

[gibsosa]

Thanks for that link!!

[FreedomOfExpression]

Thanks, I am no expert at this but doesn’t windows and antivirus SW control what computer system info gets sent back across the internet by a browser?

What about privacy mode?

I'm no expert, either. Maybe someone more knowledgeable will chime in.
I hope that future versions of the browsers would have an option to disable battery level reporting in HTML5. That would seem to be the easiest place to stop it.

[sickoflibs]

Googling this was a pain but according to this link MS IE doesn't support the Battery Status API for websites, but Chrome, Firefox,...do

03 Feb 2015, Know the Battery Status of your Visitor’s Mobile Phone

[sickoflibs]

I still question the premise that battery performance info can identify individuals out of millions of users.

Sounds very ambiguous.

More would be easily gained by IP address in most cases.

[FreedomOfExpression]

Googling this was a pain but according to this link MS IE doesn't support the Battery Status API for websites, but Chrome, Firefox,...do

Thanks!
I wonder about the next iteration of IE, the Microsoft Edge browser. I suppose I'll wait and see.

[FreedomOfExpression]

I still question the premise that battery performance info can identify individuals out of millions of users.

Sounds very ambiguous.

More would be easily gained by IP address in most cases.

By itself, that is probably true. But used in conjunction with other information, someone may be able to pinpoint down to which device you are using.

[sickoflibs]

It would be fine as long as it gives us an option to turn it off.