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  #1 Old 03-29-2015, 07:06 PM
jdoeinator
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Default Cold boot atacks encrypted disk extracation- GOOD to know in case of feds

Did you know that even if your system is whole disk encrypted, your data can still be extracted using something called a cold boot attack? Read on.
The first thing we need to talk about is RAM. RAM stands for random access memory. All you need to know about RAM is that RAM is the place in a computer where the operating system, application programs, and data in current use are kept so that they can be quickly reached by the computer’s processor. RAM is much faster to read from and write to than the other kinds of storage in a computer, the hard disk, floppy disk, and CD-ROM. However, the data in RAM stays there only as long as your computer is running. When you turn the computer off, RAM loses its data.
When you turn your computer on again, your operating system and other files are once again loaded into RAM, usually from your hard disk. RAM can be compared to a person’s short-term memory and the hard disk to the long-term memory. The short-term memory focuses on work at hand, but can only keep so many facts in view at one time. If short-term memory fills up, your brain sometimes is able to refresh it from facts stored in long-term memory. A computer also works this way. If RAM fills up, the processor needs to continually go to the hard disk to overlay old data in RAM with new, slowing down the computer’s operation. Unlike the hard disk which can become completely full of data, RAM never runs out of memory.
Data can be extracted from the RAM using various tools. When you have a text document open and you are working on it, you are working from the RAM. Meaning that if you are working on a sensitive document, that document is temporarily stored in the RAM and is vulnerable to being extracted while the computer is on. When RAM is being stored, it is being stored without any form of encryption, making it very easy to steal and a huge security risk.
Shutting down a computer through its normal shutdown cycle usually goes through a process of clearing the RAM. However, if the computer loses power abruptly like in a power outage, the computer does not go through its normal shut down cycle and some information remains on the RAM chips for a few seconds up to a few minutes. This is one of the ways cold boot attacks can work.
I also want to quickly introduce a type of RAM to you which will help you understand the rest of this article better. Below is a research paper and they used a type of ram called DRAM. DRAM stands for dynamic random access memory. DRAM is the most common kind of random access memory (RAM) for personal computers and workstations. DRAM is dynamic in that, unlike static RAM (SRAM), it needs to have its storage cells refreshed or given a new electronic charge every few milliseconds. DRAM is designed to lose its memory quickly after losing power. Then there are subsections of DRAM called DDR. This is a way of making the memory more quickly available, but it is not really important to fully understand. Wikipedia can give you all you need to know about DDR. In this article we are focusing on just the concept of DDR, DDR2 and DDR3.
These are newer versions of DRAM that keep getting better, and I believe we are currently up to DDR4. But most computers circulating around today have DDR2 and DDR3 in them unless they are older computers, this includes laptops. DRAM is known as a type of volatile memory, it is computer memory that requires power to maintain the stored information. It retains its contents while powered, but when power is interrupted, stored data is quickly lost. But how quickly is it lost?
In 2008, a group of researchers wanted to see the practicality of extracting unencrypted data from the RAM in your computer. They argued that DRAMs used in most modern computers retain their contents for seconds to minutes after power is lost, even at operating temperatures and even if removed from a motherboard. And by using an analysis tool they were able to search for key files (such as PGP keys) held in the RAM that could be used to decrypt encrypted volumes (drives) on your computer. They successfully were able to decrypt volumes using BitLocker, FileVault, dm-crypt, and TrueCrypt.
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