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Wiping a Smartphone Still Leaves Data Behind

Soulskill posted about a year and a half ago | from the why-you-always-smash-them-with-a-hammer-before-reselling-them dept.

Cellphones 155

KindMind writes "To probably no one's surprise, wiping a smartphone by standard methods doesn't get all the data erased. From an article at Wired: 'Problem is, even if you do everything right, there can still be lots of personal data left behind. Simply restoring a phone to its factory settings won't completely clear it of data. Even if you use the built-in tools to wipe it, when you go to sell your phone on Craigslist you may be selling all sorts of things along with it that are far more valuable — your name, birth date, Social Security number and home address, for example. ... [On a wiped iPhone 3G, mobile forensics specialist Lee Reiber] found a large amount of deleted personal data that he recovered because it had not been overwritten. He was able to find hundreds of phone numbers from a contacts database. Worse, he found a list of nearly every Wi-Fi and cellular access point the phone had ever come across — 68,390 Wi-Fi points and 61,202 cell sites. (This was the same location data tracking that landed Apple in a privacy flap a few years ago, and caused it to change its collection methods.) Even if the phone had never connected to any of the Wi-Fi access points, iOS was still logging them, and Reiber was able to grab them and piece together a trail of where the phone had been turned on.'"

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AND WIPING MY ASS STILL LEAVES POO BEHIND! (-1, Flamebait)

Subject Line Troll (581198) | about a year and a half ago | (#43341831)


Re:AND WIPING MY ASS STILL LEAVES POO BEHIND! (3, Funny)

Doug Otto (2821601) | about a year and a half ago | (#43342263)

Which begs the question: "How do blind people know when to stop wiping?"

Re:AND WIPING MY ASS STILL LEAVES POO BEHIND! (1)

Anonymous Coward | about a year and a half ago | (#43342397)

I know that many blind people fill cups with liquid by putting a finger in the cup, and feeling when it's full. Maybe they use the same sense of touch in this case ....... I've got to stop shaking blind people's hands.

Re:AND WIPING MY ASS STILL LEAVES POO BEHIND! (0)

Anonymous Coward | about a year and a half ago | (#43342419)

Which begs the question: "How do blind people know when to stop wiping?"

Blind people don't wipe.

Sledgehammer (1)

Anonymous Coward | about a year and a half ago | (#43341869)

That's why I used a sledgehammer and a group of beefy muscular friends to wipe mine out. 7 in fact.

Re:Sledgehammer (1)

Anonymous Coward | about a year and a half ago | (#43342019)

Sounds like a gangbang to me.

Re:Sledgehammer (1)

Lumpy (12016) | about a year and a half ago | (#43343223)

How girly... I use a 50BMG round and a binary explosive behind it.

doesn't sound like built in wipe was used (3, Interesting)

Anonymous Coward | about a year and a half ago | (#43341871)

Did the previous owner use the "erase all content and settings" feature of that phone? Or just restore it. That would have been using the built in tool and would have overwrote the data. http://support.apple.com/kb/ht2110

Re:doesn't sound like built in wipe was used (1)

Velska1 (1435341) | about a year and a half ago | (#43341969)

The idea in TFA was that the built-in wipe, IOW "erase all content settings" was used, and much was still there.

Sometimes, one could perhaps RTFA before inserting foot.

Re:doesn't sound like built in wipe was used (4, Funny)

BasilBrush (643681) | about a year and a half ago | (#43342063)

Quick, someone tell 2008 that they have a problem with phone security.

Tried to call (4, Funny)

SuperKendall (25149) | about a year and a half ago | (#43342415)

Quick, someone tell 2008 that they have a problem with phone security.

I tried to call the iPhone owners but they were all on AT&T and had no reception.

Then I tried to call all the Android owners but their batteries were all dead...

Re:Tried to call (3, Funny)

Sponge Bath (413667) | about a year and a half ago | (#43343225)

Tried to call all the Windows Phone owners, but they didn't exist.

Re:doesn't sound like built in wipe was used (5, Informative)

icebike (68054) | about a year and a half ago | (#43343003)

When you do read TFA you find out this:

Take the two Motorola devices(android). Both were wiped, and neither had much to speak of stored in their built-in memory, just some application data with no personally identifiable fingerprints.

But one user left his micro SD card in the phone. Although the contents of the card were deleted, the card had not been formatted. This, apparently, meant the files were recoverable. And because Android cached application data to this SD card, Reiber could recover e-mail data as well — enough that we could positively identify the phone’s owner via his e-mail address. But the real treasure trove was the photos and documents. The photos still had metadata, including the dates, times and locations in which the photos were shot. And while the documents were benign, if the phone’s owner had stored sensitive information on his phone — think a tax return with a Social Security number, or a .pdf bank statement — we would have had that, too.

So other than USER Stupidity of leaving his SD card in the device he recycled, this once again is an Apple story pinned to a model long out of production dating to a problem long since fixed by Apple.

Not that it changes much, if the police who buy these forensic tools happen to get your phone they pretty much have everything they need to know everything about you. How does "AccessData" get around violations of the DMCA by building tools to circumvent encryption?

Re:doesn't sound like built in wipe was used (1, Insightful)

hairyfeet (841228) | about a year and a half ago | (#43343019)

You can forget it friend, any time you get an article involving the "big three", Apple, Google, or MSFT, the apologists brigade will be out in force. It doesn't matter what TFA says, it can show with hard data that Apple is lax on security, Google is going apeshit with datamining or windows 8 makes Vista look like a hit, doesn't matter, because for some damned reason these people treat the corps like ballclubs and will rush to their defense. I used to think it was some form of buyer's remorse, you know they paid too much money for their latest toy and are now rushing to defend it so they don't feel foolish? But I've seen the same behavior when the product is free so now I have NO idea why somebody who doesn't have stock would treat some megacorp like a ballclub.

As for TFA this is something I figured would be a problem once we switched to flash memory, with every die shrink the amount of cycles the flash memory can take before dying gets worse and these companies don't want to be getting a ton of "I wiped my phone and now half the storage is gone!" complaints and returns and of course even if you DID do a full wipe with the way wear leveling works by remapping and lying to the OS I don't know how trustworthy a wipe would really be except to keep Joe Clueless who buys the thing on eBay from getting the data.

So has anybody really done any extensive testing on how easy or hard it is to get a secure wipe with flash memory? I know that supposedly when a cell fails its stuck in a "read only" state and the drive just remaps to some of the spare cells so how hard would it be to get the data off those "dead" cells anyway? At the shop I have been avoiding SSDs simply because of how many failures my gamer customers have seen from the tech (kinda reminds me of the first years of HDDs and how often they went tits up back then) but it would be nice to know how well a wipe on flash memory would actually work.

A contrived test: old phone, old operating system? (5, Informative)

perpenso (1613749) | about a year and a half ago | (#43342015)

Did the previous owner use the "erase all content and settings" feature of that phone? Or just restore it. That would have been using the built in tool and would have overwrote the data. http://support.apple.com/kb/ht2110 [apple.com]

The author used the last iPhone (3G) running the last iOS version (4) that would exhibit such behavior. It seems a contrived test.

An upgrade to iOS 5 would fix the problem on the 3G. On newer phones the encryption key needed to access the data is destroyed, so the problem never would have occurred.

Re:A contrived test: old phone, old operating syst (2)

sethmeisterg (603174) | about a year and a half ago | (#43342029)

EXACTLY. Wish my mod points hadn't expired.

Re:A contrived test: old phone, old operating syst (2)

ejasons (205408) | about a year and a half ago | (#43342145)

The author used the last iPhone (3G) running the last iOS version (4) that would exhibit such behavior. It seems a contrived test.

More than just contrived, it is very intellectually dishonest...

Re:A contrived test: old phone, old operating syst (4, Informative)

Alter_3d (948458) | about a year and a half ago | (#43342149)

The author used the last iPhone (3G) running the last iOS version (4) that would exhibit such behavior. It seems a contrived test. An upgrade to iOS 5 would fix the problem on the 3G. On newer phones the encryption key needed to access the data is destroyed, so the problem never would have occurred.

Sorry, but the iPhone 3G tops out at version 4.1.2. The 3GS, on the other hand, does have support for iOS 6, if I remember correctly.

Re:A contrived test: old phone, old operating syst (1)

Bigbutt (65939) | about a year and a half ago | (#43342185)

Yep. I have 6 on my 3GS. The first gen iPad doesn't though.

[John]

Re:A contrived test: old phone, old operating syst (1)

perpenso (1613749) | about a year and a half ago | (#43342261)

The author used the last iPhone (3G) running the last iOS version (4) that would exhibit such behavior. It seems a contrived test. An upgrade to iOS 5 would fix the problem on the 3G. On newer phones the encryption key needed to access the data is destroyed, so the problem never would have occurred.

Sorry, but the iPhone 3G tops out at version 4.1.2. The 3GS, on the other hand, does have support for iOS 6, if I remember correctly.

My bad. I might have been thinking of the iPod 3rd gen which tops out at 5.1. The iPhone 3GS (also 3rd gen) is supported by iOS 6.1, the current version.

Re:A contrived test: old phone, old operating syst (2)

organgtool (966989) | about a year and a half ago | (#43342281)

As others have pointed out, the iPhone 3G topped out at iOS 4 (and that's if you can't deal with how slowly it ran). Even if it could run iOS 5, you neglected the possibility that the person could have sold the phone before iOS 5 even came out. My iPhone 3G definitely had no such erase option and since the damn phone refuses to mount like a proper USB device, I was not able to use software from my laptop to securely wipe the phone before selling it. Oh well, at least I haven't had my identity stolen yet.

Load the 3G with music ... (2)

perpenso (1613749) | about a year and a half ago | (#43342319)

After erasing the contents fill the 3G with music to overwrite, then erase again?

Re:Load the 3G with music ... (0)

Anonymous Coward | about a year and a half ago | (#43342499)

After erasing the contents fill the 3G with music to overwrite, then erase again?

Pretty sure the filesystem in iOS can have partially empty blocks. I'd make a copy of my music, then run find . -type f -print0 | perl -n0e 'truncate($_, -s $_ >> 13 13)' to make sure that all the files were rounded off to 4096 bytes first.

There is an app for that ... (4, Interesting)

perpenso (1613749) | about a year and a half ago | (#43342595)

After erasing the contents fill the 3G with music to overwrite, then erase again?

Pretty sure the filesystem in iOS can have partially empty blocks. I'd make a copy of my music, then run find . -type f -print0 | perl -n0e 'truncate($_, -s $_ >> 13 13)' to make sure that all the files were rounded off to 4096 bytes first.

I just thought to check for apps that wipe storage, there are several. I should have known there was an app for that. :-)

Re:Load the 3G with music ... (0)

Anonymous Coward | about a year and a half ago | (#43342627)

And that's >> 13 << 13, since /.'s HTML handling is lame.

Re:A contrived test: old phone, old operating syst (2)

Jafafa Hots (580169) | about a year and a half ago | (#43342343)

But you're assuming that everyone who had an older phone ran out and ditched it the moment the new ones came out and thus there are no older iPhones with older software in use.

Oh wait... we're talking about Apple. Ok, yeah, everyone DID immediately ditch their old phone the moment the new model came out. Nevermind.

Both iPhone & Android phones less than 3 years (1)

perpenso (1613749) | about a year and a half ago | (#43342429)

But you're assuming that everyone who had an older phone ran out and ditched it the moment the new ones came out and thus there are no older iPhones with older software in use.

Oh wait... we're talking about Apple. Ok, yeah, everyone DID immediately ditch their old phone the moment the new model came out. Nevermind.

Its been nearly 3 years since the 3G has been sold. Both iPhone and Android users tend to have phones less than 3 years old.

So? (3, Insightful)

ArchieBunker (132337) | about a year and a half ago | (#43342441)

This was to prove that selling your OLD PHONE can raise security issues

Re:A contrived test: old phone, old operating syst (0)

Anonymous Coward | about a year and a half ago | (#43342647)

The author used the last iPhone (3G) running the last iOS version (4) that would exhibit such behavior. It seems a contrived test.

It's only contrived if you fail to consider that most people who are SELLING a USED iPhone on Craigslist are selling their OLD model, not the new one they just purchased.

Personally, I found the following statement the most interesting out of the entire article:
"Interestingly, many of the locations found in the database were places the phone’s owner had never been — most in southeast Asia. Reiber says this suggests the phone or its memory had been refurbished"
That's very interesting indeed.

Re:A contrived test: old phone, old operating syst (1)

Kaenneth (82978) | about a year and a half ago | (#43342779)

Or the wi-fi access point MAC address was duplicated by some cheap SE Asian company?

I'd say there is a higher probability the location data was just wrong.

Re:A contrived test: old phone, old operating syst (1)

djl4570 (801529) | about a year and a half ago | (#43342797)

No so contrived. These are the phones that are entering the used market. The early adopters are getting the next great iPhone and selling their old one. A lot of these users don't want to spend time or money upgrading the OS of an old phone and may be blissfully unaware of the security issues of the outdated OS.

Re:A contrived test: old phone, old operating syst (1)

Lumpy (12016) | about a year and a half ago | (#43343241)

It was also a iphone 3, the 3G and newer all solved this problem. The Article is horribly out of date.

Mobile Forensics Specialist (0)

Anonymous Coward | about a year and a half ago | (#43341889)

Now there is a burgeoning career field. Does this still work after clearing the cache on and Android?

Re:Mobile Forensics Specialist (0)

Anonymous Coward | about a year and a half ago | (#43342137)

You may be scarred for life after.

Social Security Number? (1, Insightful)

Anonymous Coward | about a year and a half ago | (#43341913)

Why would my phone know my social security number? Has anyone ever had to input this?

Email, of course (1)

Misagon (1135) | about a year and a half ago | (#43342735)

It could have been in an email:
* State/gov authorities.
* Insurance company.
* Your doctor
* Digital copy of payslip
etc.

Do you not have access to your email via your phone?

Re:Email, of course (1)

CCarrot (1562079) | about a year and a half ago | (#43342861)

It could have been in an email:
* State/gov authorities.
* Insurance company.
* Your doctor
* Digital copy of payslip
etc.

Do you not have access to your email via your phone?

Umm...if any company that I dealt with actually did this, I would be severing all relationships with them immediately and demanding that they remove my information from any and all databanks they use. They may actually have my SIN, as provided by me in person or via sealed snail mail when I contracted for their services, but that information should never, I repeat never be treated so casually.

No, I do not send or receive sensitive personal information such as my SIN via email. Nor do I scribble it in the dirt on my car windows...but to each their own, I suppose...

Re:Email, of course (1)

Lumpy (12016) | about a year and a half ago | (#43343275)

"They may actually have my SIN, as provided by me in person"

Hello fellow shadowrunner... is that a Corporate SIN or is it your fake SIN for your missions?

Re:Email, of course (3, Insightful)

Lumpy (12016) | about a year and a half ago | (#43343267)

In the 26 years I have had email and 12+ years I have had a smartphone I have never, EVER sent or received an email with my social security number in it.

This fear is a Capitol F in FUD.

68,000 wifi points?? (0)

Anonymous Coward | about a year and a half ago | (#43341935)

take the point of the article, as it were, but you'd have to move pretty fast for 68,000 wifi points that you had connected to. pretty fast.

Re:68,000 wifi points?? (1)

detritus. (46421) | about a year and a half ago | (#43342001)

Or drive a few miles around Manhattan.

Re:68,000 wifi points?? (3, Informative)

jxander (2605655) | about a year and a half ago | (#43342075)

Some napkin math, assuming he purchased the phone in July 2008 when 3G went on sale, and it's been in use constantly for the last 57 months ... and ball-parking 30 days/month ... he hit 40 Wi-Fi points and 36 cell towers every day.

Even with the assumption that these are not unique access points (i.e. his home WiFi is counted 3 or 4 times a day, depending on how often he comes and goes) ... that's still an insane number. If we change the time-frame to 2 years, roughly the average lifespan between upgrades, he's up to 95 WiFi points per day.

Quite the busy bee.

Re:68,000 wifi points?? (4, Insightful)

EvanED (569694) | about a year and a half ago | (#43342163)

Even with the assumption that these are not unique access points ... that's still an insane number. If we change the time-frame to 2 years, roughly the average lifespan between upgrades, he's up to 95 WiFi points per day.

If the wifi points are non-unique, 100 wifi points per day would be downright easy to achieve. I probably pass far more than that on the way to and from work each day on the bus.

Remember, it's not "how many networks have you connected to" but "how many have come in range of your antenna."

Unique points would be a lot harder to hit, but as someone else points out, you could probably rack up access points very quickly in a metropolitan area.

Re:68,000 wifi points?? (1)

compro01 (777531) | about a year and a half ago | (#43342437)

Some napkin math, assuming he purchased the phone in July 2008 when 3G went on sale, and it's been in use constantly for the last 57 months ... and ball-parking 30 days/month ... he hit 40 Wi-Fi points and 36 cell towers every day.

Not that difficult. Just sitting at my desk, my Galaxy S3 picks up 36 Wi-Fi networks. I probably walk past that many again on my way to work. And a few dozen more any time I walk into an apartment building.

I consider it rather mystical how any Wi-Fi network is able to function at all with this amount of crowding in the channels.

Re:68,000 wifi points?? (1)

xaxa (988988) | about a year and a half ago | (#43343057)

I see 11 access points sitting at home, in a chunky brick building. If I take the metro into central London I go past 10 access points just underground (in the stations, and that's only the public ones).

Heading straight home gives another 10 + 11, so that's already over your average.

(My own router's signal doesn't reach from one end of the flat to the other, due to the chunky walls, and most of the 11 signals I see are very weak, so I probably hit 5-10 see-you see-you-nots just going to the kitchen and back.)

I actually cycle to work. I wonder if my phone has enough time to detect all the residential connections I go past? I doubt it, but there should be enough slow bits (corners, junctions) to plot my route exactly.

Re:68,000 wifi points?? (1)

sjames (1099) | about a year and a half ago | (#43343143)

Or he rides the train. In addition to the fleeting contacts from outside, there's people tethering on the train.

It's still quite a lot, but I suppose it's vaguely possible.

Re:68,000 wifi points?? (1)

adolf (21054) | about a year and a half ago | (#43343519)

Since I got an OG Droid in November of 2009, I've purposefully observed 132,205 non-unique access points just in the course of normal short traveling for work and pleasure, exclusively by car.

I am unsurprised by any of these figures.

This wouldn't be an issue... (1)

Anonymous Coward | about a year and a half ago | (#43341973)

This wouldn't be an issue if cell phones were unlocked and the firmware and OS was GPLed.

Can't hide it (1)

Jeremy Morales, CEH (2886313) | about a year and a half ago | (#43341975)

Without the development of a secure wipe tool for mobile devices, all your information is easily available to retrieve as long as you know what you are doing. Look up tools like FTK or Encase.

Re:Can't hide it (4, Informative)

BasilBrush (643681) | about a year and a half ago | (#43342045)

With iOS it certainly isn't. Note the iPhones used in the article were deliberately selected to be very old. iPhone 3G.

With newer iPhones, every single byte is written using a hardware based encryption key. AES-256. Wiping the phone involves deleting just the key. At that stage none of the phone's data is recoverable. Not by anyone.

Re:Can't hide it (1)

Jeremy Morales, CEH (2886313) | about a year and a half ago | (#43342093)

That is partially correct, modern forensics tools (like FTK) can fight back.

Re:Can't hide it (1)

h4rr4r (612664) | about a year and a half ago | (#43342119)

How exactly do you fight back against AES?

Re:Can't hide it (1)

Jeremy Morales, CEH (2886313) | about a year and a half ago | (#43342147)

Re:Can't hide it (2)

h4rr4r (612664) | about a year and a half ago | (#43342203)

Only if you are so stupid that your PIN is only 4 numbers and you allow unlimited retires. I am pretty sure iOS now makes the retry interval longer and longer to avoid this attack.

They just brute force it, that is not anything special.

Re:Can't hide it (0)

Anonymous Coward | about a year and a half ago | (#43342891)

That counts for manual retries. iOS connected to the machine and brute forcing through USB cable doesn't have limit and is pretty fast.

Re:Can't hide it (1)

Lumpy (12016) | about a year and a half ago | (#43343305)

And did not reset the phone. you cant brute for a pin when the key is completely deleted.

Re:Can't hide it (2)

PhunkySchtuff (208108) | about a year and a half ago | (#43342359)

If you have it set, the device PIN unlocks the AES key that decrypts the phone's filesystem.
If you allow unlimited guesses at the PIN, you can unlock the AES key and decrypt the filesystem.

If you erase the phone (reset all content and settings) the phone securely wipes it's AES key - the filesystem is from that point forwards nothing more than random data. If you have an attack against AES256 then you stand a chance at recovering something, but you don't...

There's no use in guessing the PIN as the encryption key that the PIN unlocks has been erased.

Re:Can't hide it (1)

the_B0fh (208483) | about a year and a half ago | (#43342515)

Do you even understand what you just cited? That has *NOTHING* to do with an iPhone 3GS and onwards that was wiped.

Once wiped, it is not recoverable. The key is gone. Please learn and understand your tools and limitations.

Re:Can't hide it (1)

Kaenneth (82978) | about a year and a half ago | (#43342805)

Barring a weakness in the key generator; iirc that was how the PS3 was cracked?

No "Fight back" once key is gone (0)

SuperKendall (25149) | about a year and a half ago | (#43342199)

You can't "fight back" when the encryption key has been discarded. It is gone.

That misunderstood article is about how to get data off a device that has NOT been wiped.

Re:No "Fight back" once key is gone (2)

Jeremy Morales, CEH (2886313) | about a year and a half ago | (#43342547)

I just talked to the forensics guys I know, I was wrong. And you are correct.

Re:Can't hide it (1)

Lumpy (12016) | about a year and a half ago | (#43343295)

That is 100% false. Any "digital Forensics" person claiming that is a big far liar that has no clue at all to how it works or how even computers work.

If someone you know told you that, you need to have them show you proof.

Depends on the phone and the methods used (4, Informative)

guruevi (827432) | about a year and a half ago | (#43341977)

Most decent cell phones have built-in encryption which wipes the phone by simply deleting the built-in keys. Some cheap-ass droids and the 'feature-phones' may not have it built-in but it's fairly easy to wipe a phone that has the feature.

Off course, if you use the wrong methods (such as simply 'restoring' the phone) or using unencrypted external media, not much is going to help you. If you really need to get rid of your data (eg. in an enterprise environment) I would hope those in charge of the devices would know how to configure and manage the phones correctly so they can be remotely wiped etc

Re:Depends on the phone and the methods used (3, Informative)

Anonymous Coward | about a year and a half ago | (#43342223)

The bad news is that only since Android 4.0 that there has been decent encryption in devices. Before that, only some Motorola devices had some ability to encrypt the SD card and the main filesystems.

The good news is that Android has grown up, and uses dmcrypt to encrypt the /data partition. One can even have the passphrase that decrypts the filesystem separate from the screen unlocking PIN, using a command line and the vdc cryptfs changepw command. This way, if the device falls into the wrong hands and gets power-cycled, an attacker has to guess a 20+ character passphrase as opposed to a 4-8 digit PIN.

The ugly: Just the /data filesystem is encrypted. If you have a SDcard, you are SOL unless you have a Motorola device that has their own file based mechanism of writing encrypted data.

As for iOS, AFAIK, it mainly relies on hardware chip voodoo to only allow access to the AES key once the chip validates the PIN, and to mitigate an attack against just four digits (which is the typical PIN code length.) If one of the chips has a weakness, game is over.

With the latest devices, both iOS and Android are decently secure, except both have strengths weaknesses. Android can be set to have a reasonably strong passphrase, then use a PIN once /data is mounted. However, Android can't encrypt SD cards. iOS is encrypted immediately, but the downside is that the OS relies on magic smoke ASICs to enforce its security.

Re:Depends on the phone and the methods used (1)

h4rr4r (612664) | about a year and a half ago | (#43342375)

If you are reselling the device just remove the SD card, or stick it in a PC and use DD to write /dev/urandom to it. Obviously some users will find the latter approach too technical, or not trust SD cards enough, so selling it without an SD card is a fine solution.

Re:Depends on the phone and the methods used (1)

gl4ss (559668) | about a year and a half ago | (#43342567)

that just takes care of the sdcard though and leaves the internal rom untouched. wiping that is a possibility too though.

doesn't sound like the phone in the article was wiped at all though.

Re:Depends on the phone and the methods used (0)

Anonymous Coward | about a year and a half ago | (#43343479)

Most decent cell phones have built-in encryption which wipes the phone by simply deleting the built-in keys.

Blackberries go further, by repeatedly overwriting the data. So if the key was weak, or recoverable, you still can't get the data.

This is old news, and no longer correct for iPhone (5, Informative)

kallisti (20737) | about a year and a half ago | (#43341997)

The key line: "On a wiped iPhone 3G"

Starting with the iPhone3GS, iOS encrypts everything with a random AES256 key. When you say to wipe the device, it erases that key rendering everything else unusable. This is mentioned in the article, but downplayed. It's been a long time since you could even buy an iPhone 3G, so it seems alarmist to bring it up now.

http://blog.itsecurityexpert.co.uk/2011/10/securely-wiping-your-personal-data-from.html [itsecurityexpert.co.uk]

Re:This is old news, and no longer correct for iPh (1)

Jeremy Morales, CEH (2886313) | about a year and a half ago | (#43342039)

http://www.accessdata.com/products/digital-forensics/mobile-phone-examiner [accessdata.com] On-the-Fly Decryption of Operating System and Logical Data of iOS

Re:This is old news, and no longer correct for iPh (0)

Anonymous Coward | about a year and a half ago | (#43342089)

I'm guessing that only works if the phone wasn't reset to factory settings.

Re:This is old news, and no longer correct for iPh (0)

SuperKendall (25149) | about a year and a half ago | (#43342179)

What part of "wipe device resets the key" did you not understand? You can't recover anything if the key is discarded. That article only matters for police who have recovered iPhones from criminals and want to try and get something out, not people who are selling a phone and reset it beforehand.

Re:This is old news, and no longer correct for iPh (1)

the_B0fh (208483) | about a year and a half ago | (#43342551)

How many times are you going to quote that article without understanding WTF you're quoting? And you call yourself a CEH?

Jesus Christ.

Re:This is old news, and no longer correct for iPh (2)

Jeremy Morales, CEH (2886313) | about a year and a half ago | (#43342807)

Actually, I was wrong, I misunderstood somethings. Not afraid to admit I was wrong.

Re:This is old news, and no longer correct for iPh (0)

Anonymous Coward | about a year and a half ago | (#43343001)

Is this encryption key stored in multiple places on the device? In case of accidentaly corruption or hardware error?

Also, another question. Is the encryption key backedup onto the computer when you make a backup, or is the device the only copy in existence anywhere of they key?

Who the hell keeps their Social Security number (1)

Spy Handler (822350) | about a year and a half ago | (#43341999)

on their phone??

Re:Who the hell keeps their Social Security number (0)

Anonymous Coward | about a year and a half ago | (#43342155)

I need that to update my flash player and access my Nigerian bank accounts. Duh

Re:Who the hell keeps their Social Security number (1)

PyroMosh (287149) | about a year and a half ago | (#43342157)

For real.

I get why that could be a problem with a PC. After all, it's not unusual to file one's taxes on one's PC, or have other records that might include one's SSN on a PC. But who the hell is doing anything like via a phone?

Re:Who the hell keeps their Social Security number (1)

h4rr4r (612664) | about a year and a half ago | (#43342317)

TurboTax and other have products that work on smartphones and tablets. I do not believe they save anything like that locally though.

Re:Who the hell keeps their Social Security number (0)

Lumpy (12016) | about a year and a half ago | (#43343315)

You would have to be completely insane to do your taxes on your phone.

Newer phones (3, Interesting)

Selfbain (624722) | about a year and a half ago | (#43342017)

I'd be more interested to see if he can still do it on a newer model. The earlier models of iPhones were well known to have poor security.

Sigh... (1)

pushing-robot (1037830) | about a year and a half ago | (#43342033)

we rounded up every old phone we could scrounge up from around the office and asked the owners to wipe them. Our stash consisted of two iPhone 3G models, two Motorola Droids, an LG Dare and an LG Optimus.

There were similar discrepancies in what Reiber found on the two iPhones, although both were 3G models running iOS 4

It’s worth noting that the iPhone 3GS and newer versions use a hardware encryption key which is deleted when the phone is wiped, but data was easily recovered from these older models.

Oh no! Five-year-old* long-discontinued phones running old OSes lack security! The horror!

* okay, the Droid is only 4 years old, and the Optimus a mere 3. (And both shipped with Android 2.0 or earlier.)

Can we please be more specific? (1)

MyFirstNameIsPaul (1552283) | about a year and a half ago | (#43342041)

'Smartphone' is a general term, but this article is about specific smartphones. "Our stash consisted of two iPhone 3G models, two Motorola Droids, an LG Dare and an LG Optimus. (We had hoped for a BlackBerry, but nobody had one.)" As usual, BlackBerry is not only excluded from the test, but the technology 'journalists' had to throw in a swipe at BlackBerry, which, to me, is an admission of their own incompetence. A BlackBerry device probably would pass the test with flying colors, just as these devices do with most every security test. I'm not claiming that BlackBerry should be best selling phones or that they are the greatest ever, just that credit should be given where it is due.

Re:Can we please be more specific? (1)

h4rr4r (612664) | about a year and a half ago | (#43342159)

Or maybe it reflects the fact that few people still use them, and nearly no one would if they had a choice.

Most modern smartphones support good encryption. Just use that.

Re:Can we please be more specific? (1)

MyFirstNameIsPaul (1552283) | about a year and a half ago | (#43342661)

So your argument is that the LG Dare is a more popular phone and platform than BlackBerry? You are wrong.

Re:Can we please be more specific? (0)

Anonymous Coward | about a year and a half ago | (#43342349)

A BlackBerry device probably would pass the test with flying colors

So would a Motorola DynaTAC.

Enable Encryption after the fact (0)

pavon (30274) | about a year and a half ago | (#43342059)

I've read in a few places that if you enable encryption on either Android or an iPhone, it encrypts the entire flash chip at a low level, which has pretty much the same effect as writing a disk with random data if you don't know the key. These articles therefore recommended the following process to sanitize your phone before reselling/discarding it:
1) Enable encryption
2) Perform a factory reset/wipe
3) Disable encryption
4) Repeat if paranoid
That way all your data is deleted, and all "deleted" files are scrambled and impossible to recover if you don't have the key.

It doesn't look like researchers looked at phones where that had been performed.

Sentence doesn't make sense! (1)

bogaboga (793279) | about a year and a half ago | (#43342061)

While referring to getting all data erased.

'Problem is, even if you do everything right, there can still be lots of personal data left behind.

Wouldn't that mean you just didn't do everything right? Huh?

Google doesn't help matters by providing no avenue for de-linking one's no-longer-owned device from an existing [Google Play] account. Sad.

Re:Sentence doesn't make sense! (1)

JStyle (833234) | about a year and a half ago | (#43342587)

To remove your Google account (and therefore Google Play) from an android phone, you simply log out of the Google account. The Play Store is useless then. A factory reset (available on all androids I've used/seen), does the same, to a further degree (removing apps, etc).

Re:Sentence doesn't make sense! (2)

bogaboga (793279) | about a year and a half ago | (#43342641)

I guess I didn't make myself clear...Let me rephrase:

If you destroy your 1st Android phone and obtain a second one, there's no way of removing any reference to the 1st phone from Google Play. Or is there? I have 7 devices listed, six of which I no longer own. How do I prevent them (the six I no longer use), from getting listed on Google Play? Got it?

Vague useless article. (3, Informative)

Andy Dodd (701) | about a year and a half ago | (#43342085)

The article makes no mention of WHICH Android revision each of the given phones tested was using.

It was a known problem with Gingerbread and earlier that the wipe method used by most Android devices was insufficient. That's why Google added secure erase prior to reformat with ICS (maybe HC too, not sure...)

https://android.googlesource.com/platform/system/extras/+/c2470654d4b4db09a7052fc5fa108ac21f1b1948 [googlesource.com]

Interesting result of this: Samsung's eMMC chips that were shipped in the Galaxy S II and original Galaxy Note couldn't handle this secure erase command properly, and using a standard "secure" wipe had a pretty good chance of corrupting the wear leveller so badly the chip would be rendered useless. (Samsung's own recoveries were "neutered" so as not to issue a secure erase command.)

TL;DR - Unless crippled by the manufacturer, any recent Android device (ICS or newer) should not have any of the issues with data remaining easily recoverable after a wipe described by this article. LG didn't do anything special here - they just implemented ICS or later and that's all that was needed.

SO what do you need to be sure? (1)

the eric conspiracy (20178) | about a year and a half ago | (#43342171)

Van der Graaf Generator?
Oxy-acetylene torch?
Cement kiln?

I know what to do with a hard drive (DBAN followed by drill press) and a DVD (shredder).

Re:SO what do you need to be sure? (1)

Nerdfest (867930) | about a year and a half ago | (#43342237)

Nuke it from orbit. It's the only way to be sure.

Putting the article asside for a moment... (1)

ADRA (37398) | about a year and a half ago | (#43342205)

How the hell on EARTH do you have "61,202 cell sites" without de-duping?

Then I checked the US wireless quick facts and found:
June-12 June-07 June-02 June-97
285,561 210,360 131,350 38,650

Yikes, that's quite the expansion... but regardless, it still means this phone would've travelled through a very large number of dense American cities to get up to that count.

easy solution (0)

Anonymous Coward | about a year and a half ago | (#43342211)

just stick the phone in a degausser......

Erase HD (0)

Anonymous Coward | about a year and a half ago | (#43342299)

Erase hard drive= sledgehammer+fire.

big surprise here... (0)

Anonymous Coward | about a year and a half ago | (#43342383)

even in an ssd or usb storage device, flash memory is a bugger to erase... and to know with absolute certainty that the data is indeed gone, requires destruction, not deletion.

theres only one way to wipe discarded hardware (1)

FudRucker (866063) | about a year and a half ago | (#43342539)

pound it to smithereens with an 8 pound sledge hammer, nothing but crumbs left when i am done

I teach mobile device forensics (0)

Anonymous Coward | about a year and a half ago | (#43343103)

And all I can say is "DUH!" This is nothing new. The iPhone 3 did not have the built-in support to encrypt the personal data partition used on the phone, because that feature did not exist on the iPhone until iOS version 4, which coincided with the release of the iPhone 4. The iPhone 3 could not be upgraded to iOS 4.x, though the 3GS could, so this is no big surprise. Fun fact: when you wipe a iOS 4.x and later device, it doesn't actually wipe the data. What it does is destroys the encryption key for the encrypted partition, rendering it unreadable.

So don't sell it but (1)

kilodelta (843627) | about a year and a half ago | (#43343193)

Destroy it instead. It's enormously gratifying to reduce a smart phone to powder. And try reading that.

Sigh. Again, for real security, get a blackberry (2, Informative)

Anonymous Coward | about a year and a half ago | (#43343415)

Once again, blackberries solved this problem about 10 years ago (or more).

If you want real, audited, certified security, get a blackberry.

If security isn't important to you, android & iphone are fine.

Sadly, most people are in the latter category.

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