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55 comments

What do you get from sitting on the ice too long? (5, Funny)

DFurno2003 (739807) | about a year ago | (#42895285)

Polaroids Get it?

Slashdotted (0)

Anonymous Coward | about a year ago | (#42895301)

The only thing frozen here is their webserver! amirite?

Re:Slashdotted (1)

Skapare (16644) | about a year ago | (#42896195)

This is what you get when your freezer, refrigerator, toaster, or coffee maker gets slashdotted.

Wearing high heels helps for enemas (-1)

Anonymous Coward | about a year ago | (#42895319)

Even for men! Pick the highest heels you can find and use them for when you give yourself enemas.

Soft fruit enemas are especially helpful and it's a fun part of the day when you administer a yogurt enema while eating yogurt!

You can image you are a dinosaur being ravaged by a TRex - and roar like one.

Why do freezers always seem to help recover data? (5, Informative)

nefus (952656) | about a year ago | (#42895409)

As far back as the late 1980's we used freezer's on hard-drives to recover data. It helped against various over-heating issues so you could recover just a little bit more data each time you used the drive. Every few years you hear about some other method to recover data with a freezer including putting a device in the freezer. Funny how it always works. All hail the freezer!

Re:Why do freezers always seem to help recover dat (2, Funny)

Anonymous Coward | about a year ago | (#42895477)

You can't handle the stone cold truth.

Re:Why do freezers always seem to help recover dat (2)

DFurno2003 (739807) | about a year ago | (#42895483)

Honestly, My refrigerator comes in 2nd in my life, just after the dog, and before the wife.

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42896133)

Funnily enough I store my dog, my wife and also my come in my refrigerator.

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42903105)

That's funny because I store my come in your wife.

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42897015)

My refrigerator comes in 2nd....before the wife

Why do women always get married in white? Because it's always good
  when the cooker, dish washer match the rest of the appliances!!!!!

Re:Why do freezers always seem to help recover dat (5, Informative)

Anonymous Coward | about a year ago | (#42895635)

To expand on why this works.
The RAM in a phone is dynamic RAM.
It does not store data when unpowered, but needs that data to be periodically refreshed many times a second.
It turns out, that especially when cooled, the RAM may in fact retain information for some period short enough to allow the device to be unpowered and repowered, and essentially retain all its data. (there may be a few errors).

This, combined with booting into a new OS which then allows you to dump or do other things to the RAM enables the attack.

Re:Why do freezers always seem to help recover dat (3, Interesting)

CanHasDIY (1672858) | about a year ago | (#42895713)

FTR, this concept was demonstrated by Darren Kitchen on a 2009 episode of Hak5. [hak5.org]

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42895781)

FTR, it was not. Hak5 is a script kiddie vlog. They don't come up with new hacks, they show how to do what others came up with.

Re:Why do freezers always seem to help recover dat (3, Insightful)

bhcompy (1877290) | about a year ago | (#42895877)

He didn't claim they came up with a new hack. He said they demonstrated the concept. Words mean things.

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42896365)

I guess I'm used to higher standards of academic honesty, where the original source and not some copycat is referenced.

Re:Why do freezers always seem to help recover dat (1)

bhcompy (1877290) | about a year ago | (#42897115)

Again, no one here here claimed they came up with it. There is no "academic honesty" in play. Purely for demonstration purposes only. Do you fault the science teacher for demonstrating a concept he didn't come up with? Is that academic dishonesty? And that's ignoring the fact that the article that demonstrates it gives credit and links to the original study. Keep on keepin' on, AC

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42897765)

People rightfully call "blogspam" when somebody posts a link to a blog instead of the original story. This is the same thing.

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42899575)

People rightfully call "blogspam" when somebody posts a link to a blog instead of the original story. This is the same thing.

It was the original public demonstration, as far as I can tell. So stop with the butthurt posts, you tried to bash someone, you were wrong, got called out for it, and seem to have a problem just letting it go.

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42901641)

The original researchers already demonstrated the technique in their own video. You may be a fan of Darren's, but that link is still spam.

Re:Why do freezers always seem to help recover dat (1)

CanHasDIY (1672858) | about a year ago | (#42910585)

The original researchers already demonstrated the technique in their own video. You may be a fan of Darren's, but that link is still spam.

Then don't go to it, douchenozzle.

Really.

Re:Why do freezers always seem to help recover dat (0)

Anonymous Coward | about a year ago | (#42897059)

Skibbety boop snig snock wilk wack.

Re:Why do freezers always seem to help recover dat (4, Informative)

tlhIngan (30335) | about a year ago | (#42896493)

It turns out, that especially when cooled, the RAM may in fact retain information for some period short enough to allow the device to be unpowered and repowered, and essentially retain all its data. (there may be a few errors).

Actually, the period can be quite significant. One of my projects involved a kernel that could only dump messages to RAM. To get it out, I'd reboot the board and dump the log buffer. At regular room temperature, but elevated board temperature (jthe CPU was running for a good tilt so the board heated up), a power cycle (under 1s) would let you read it out perfectly. After 10s off, you could see corruption but was mostly readable. After 30s or so, it was barely readable.

It appears the main physical phenomena is that the memory capacitors "distort" ever so slightly so the RAM doesn't completely powerup randomly, but is influenced by what was held there previously. It's a time related thing as well - a memory cell that was rapidly cycled would tend to have a lower time before corruption than a cell which held data staticly for a long time. Since encryption keys tend to fall in the latter, the memory tends to stay that way a bit longer (unless the code periodically switches memory buffers and scrubs the old one - it doesn't take much - just store a new pattern in then and it'll overwrite the old one).

Sections 7 and 8 of the famous Gutmann paper [auckland.ac.nz] detail this effect in memory as well (you may recall the paper dealt with recovery of data off hard drives - but it also dealt with semiconductor nonvolatile memory as well).

A followup paper(PDF) [cypherpunks.to] goes into more detail on semiconductor memory including flash storage.

Re:Why do freezers always seem to help recover dat (1)

mlts (1038732) | about a year ago | (#42899835)

I remember this being described years ago in PGP Desktop's [1] owner's manual. What the PGP program (pgpserv.exe) did was keep two copies of RAM resident keys, one normal, one bit-inverted (XOR all 1s.) Periodically the program would flip the copies.

[1]: When PGP, the commercial product was split from McAfee and was run by an independent company before becoming part of Symantec.

Re:Why do freezers always seem to help recover dat (3, Funny)

jader3rd (2222716) | about a year ago | (#42895647)

We should ask Han Solo if it works as well with human memory too.

Re:Why do freezers always seem to help recover dat (1)

Anonymous Coward | about a year ago | (#42895963)

We should ask Han Solo if it works as well with human memory too.

Of course it does. Didn't you know that is why people are blind for a short time after being removed from carbonite? It is so that forensic investigators can retrieve information from their visual cortex and optic nerves before it gets overwritten. Also hibernation sickness is caused by overheating in the brain caused by bulk memcpy grabbing all the data from the person's memory.

Re:Why do freezers always seem to help recover dat (1)

L4t3r4lu5 (1216702) | about a year ago | (#42895649)

I can't talk about your non-volatile storage issues, but cooling a system down slows state change, meaning it's more likely to stay in its current state for longer. This means you have more time to recover whatever it is you're looking for before the volatile nature of the system means the data is lost for good.

Re:Why do freezers always seem to help recover dat (2)

EdZ (755139) | about a year ago | (#42896787)

The two work by different methods.
In the case of RAM, reducing the temperature lowers the leakage current of the capacitors in DRAM that actually store your bits, increasing the time before the charge drops below a detectable level (i.e. increasing the time before the data becomes unreadable).
In the case of HDDs, freezing them causes metal components to shrink slightly, so any seized bearings may be freed up for long enough to recover data.

Maybe (-1)

Anonymous Coward | about a year ago | (#42895507)

I don't want other people uncovering my personal data using a freezer. Does this mean I can't protect my personal data at all?

Amazing! (3, Funny)

crashumbc (1221174) | about a year ago | (#42895525)

People with physical access to a device and time, can overcome security...

Some one call the press!

Re:Amazing! (5, Insightful)

Anonymous Coward | about a year ago | (#42895603)

I guess the point is that this is an unnecessary hole in the security. The boot loader should not load anything without first wiping the RAM. The attack depends on the ability to boot into fastboot mode, which is then used for flashing a new recovery ROM, and that is booted as well without clearing the RAM. There is no normal situation where a booting system should have access to the previous RAM contents, so wiping the RAM first thing in the boot loader is a safe thing to do.

Re:Amazing! (1)

Anonymous Coward | about a year ago | (#42895675)

Some embedded systems use RAM for crash log for recovery, so while it does not make sense in a mobile, it is used and really useful in real life. Writing to RAM is at least 2 order of magnitudes faster than FLASH and not you do not have to have to worry about wear cycles.

Re:Amazing! (1)

chowdahhead (1618447) | about a year ago | (#42895957)

They acknowledge that bootloader must be unlocked for this to work though. That's really going to limit the utility of their procedure. Non-Nexus bootloaders are generally locked and encrypted, and the ADB whitelist feature of 4.2.2 should make stock Nexus devices a tough target.

Re:Amazing! (1)

BradleyUffner (103496) | about a year ago | (#42897379)

They acknowledge that bootloader must be unlocked for this to work though. That's really going to limit the utility of their procedure. Non-Nexus bootloaders are generally locked and encrypted, and the ADB whitelist feature of 4.2.2 should make stock Nexus devices a tough target.

Even Nexus devices ship with locked bootloaders by default. They can be unlocked by a simple ADB command, but this erases everything on the device.

Re:Amazing! (0)

Anonymous Coward | about a year ago | (#42899395)

There's even a big warning when you try to unlock the bootloader that it's going to wipe your data.

Re:Amazing! (1)

kllrnohj (2626947) | about a year ago | (#42901511)

Wiping the RAM each boot is a waste of time - nobody does that. I'd rather have the normal scenario be "boot quicker", not "protect me from an unreasonable scenario *if I've already unlocked my bootloader*"

If for some reason you need that extra security unlock the bootloader and replace it with one that wipes the RAM on boot. But you still won't be secure from the guy that just wires into the RAM chips directly and dumps them.

Re:Amazing! (0)

Anonymous Coward | about a year ago | (#42902049)

Wiping the small amount of RAM that even modern cellphones have doesn't take a long time. That RAM is also typically package-on-package RAM, with no exposed connectors that anyone could "wire into". Cold boot attacks are a very real possibility at places like border checkpoints.

Security (1)

Anonymous Coward | about a year ago | (#42895645)

Quite possibly the best line
"To break disk encryption, the bootloader must be unlocked before the attack because scrambled user partitions are wiped during unlocking."

Re:Security (1)

wonkey_monkey (2592601) | about a year ago | (#42895847)

So what you're saying is, if I build a secret compartment inside my neighbour's house and camp out there, I can beat him to the doormat in the morning and read all his mail? For free?

4-digit PIN (2)

j-turkey (187775) | about a year ago | (#42896171)

Admittedly, I have never used Android device encryption and do not know the specifics of how it works. However, reading the article, what is the big deal about brute forcing a 4-digit PIN on a device that one has local access to? Could the encrypted FS be dumped and brute forced in software? What am I missing?

Re:4-digit PIN (1)

j-turkey (187775) | about a year ago | (#42896427)

To answer my own question, my assertion was correct [blogspot.com] . With physical access to the device, brute forcing the PIN protecting the disk encryption is trivial. The million dollar question is: how to sufficiently protect a key in a manner that can be quickly and conveniently unlocked by an average user?

Re:4-digit PIN (0)

Anonymous Coward | about a year ago | (#42896719)

1. Store the actual key on a remote server that requires the pin to release it; after 5 attempts, the remote server locks it until a longer secret password is sent.
2. Use a 8-16 symbol password instead of a PIN

Re:4-digit PIN (1)

splatter (39844) | about a year ago | (#42897209)

"Use a 8-16 symbol password instead of a PIN"

Agreed and this is for all encrypted phones not just android. Also if the phone supports it set it up to delete the phones contents after X amount of failed attempts.

Re:4-digit PIN (1)

spazdor (902907) | about a year ago | (#42900903)

in a manner that can be quickly and conveniently unlocked by an average user?

Re:4-digit PIN (1)

splatter (39844) | about a year ago | (#42912173)

"in a manner that can be quickly and conveniently unlocked by an average user?"

Not sure why I'm bother answering this obvious troll but then use 6 characters. That still brings up the complexity /strength enough to make unbreakable before the limit hits. Please do some reading if you want protection there is some required effort above and beyond a 4 digit number PIN, it's a risk assessment for the OP to make.

http://en.wikipedia.org/wiki/Password#Memorization_and_guessing [wikipedia.org]
http://en.wikipedia.org/wiki/Password_strength [wikipedia.org]

Re:4-digit PIN (1)

mlts (1038732) | about a year ago | (#42899887)

On this subject, what would be nice would be to have both a PIN and a symbol password.

The first time the Android device powers up, it will prompt for the longer version. After that, it can use that version, or a short PIN.

Of course, another solution is to do similar to Apple, and have a dedicated chip (or in Apple's case, have it be part of the custom CPU) which stores the volume decryption key in a physically tamper-resistant place and acts as a gatekeeper. That way, accessing the stored password hash would require the facilities of a modern chip fab.

Re:4-digit PIN (1)

sosume (680416) | about a year ago | (#42901697)

Either, that, or fiddling with the emergency dial function and the on-off button, which seems to work as well ..

Re:4-digit PIN (0)

Anonymous Coward | about a year ago | (#42899587)

Face unlock!

Re:4-digit PIN (0)

Anonymous Coward | about a year ago | (#42904527)

Use different passwords/pins for encryption and screen lock. First, set your screen lock how you'd like. Encrypt your device. Then run this command to change your encryption password to something secure: "vdc cryptfs changepw <new_password>". On boot the device will ask for the more secure encryption password, but you can still use a 4 digit PIN as a screen lock afterwards.

smartphones.. cmon (0)

Anonymous Coward | about a year ago | (#42901967)

i cant believe everyone is still buying into all the smart phone hype. remember when all the conspiracy nuts were freaking out over being implanted with microchips to be tracked and monitored and what have you... MORE DOTS .... seriously though, throw this shit out untill there is a real open source publicly audit-able and modifiable solution to storing your lifes worth of data ON YOUR PERSON. dumb dumb dumb dumb dumb

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