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114

RAM is used to store sensitive non-persistent information in a lot of cases. Encryption keys would be a common example. Sometimes it is possible to remove RAM and place it into another device to dump the contents - often with the aid of liquid nitrogen. For more information, see the Wikipedia article for Cold Boot Attack.


85

Summary: There's probably some BS marketing going on, but on the whole they probably are making the more privacy-respecting laptop they can. Other answers mention other brands of privacy-focused laptops that avoid Intel chips in favour of 100% libre hardware, but you take a big performance and cost hit for doing it, because, well, Intel is the market leader ...


63

This 2013 article analyses retention time for several DRAM chips. Among the relevant information, one may list the following: Retention time depends on a lot of things, including the values of neighbouring bits. A DRAM bit is a potential well, and it loses its contents by moving charges from or into neighbouring areas, so whether there is room in these ...


49

I'm choosing to assume you're asking why it's a risk rather than how to hack. GPUs are very good at parallelising mathematical operations, which is the basis of both computer graphics and cryptography. Typically, the GPU is programmed using either CUDA or OpenCL. The reason they're good for brute-force attacks is that they're orders of magnitude faster than ...


47

People have given great answers here that directly answer your question, but I'd like to give a complementary answer to explain more in depth why GPUs are so powerful for this, and other applications. As some have pointed out, GPUs are specially designed to be fast with mathematical operations since drawing things onto your screen is all math (plotting ...


42

Well "impossible" is impossible to prove which is why in the linked answer I said "almost impossible", maybe even that is overstating it. By using a secure hardware device the attack vector goes from "malware installed remotely on host steals secret," to "attacker needs to physically gain access to the hardware device and destructively remove the private ...


42

There is nothing stopping an attacker from putting a powerline ethernet transceiver as well as a USB-enabled microcontroller into a USB charger. This would allow them to communicate with the charger in the hope to offload some malware onto a smartphone plugged into that port. However, such a device would need to be highly specialized and specifically ...


40

Yes, if an attacker has physical access to your computer it is no longer your computer. While it's theoretically possible to implement spying directly in silicon on a modern CPU, a modern x86-based CPU is extremely complicated. An attacker would be better off using a peripheral device that uses something like USB which exposes certain interrupts in an easily-...


26

If you log in somewhere (say in a browser, or some application), the password you typed in is temporarily stored in RAM for comparison against the correct password. Most applications assume the RAM is secure and don't clear everything, so it could (and often does) happen that your RAM memory contains passwords and privacy-sensitive data. Now RAM is said to ...


25

It really depends upon the specific threats you may be facing, the direction of your data transfers, etc. USB specific dangers You mention the dangers of USB. The main one is indeed related to its firmware opening the possibility of a BadUSB type attack. When you need to transfer data in both directions, you may therefore prefer to use SD-Cards which are ...


24

Yes, binary blobs are a security risk, as any other proprietary software that you cannot audit. I wouldn't call all systems using proprietary software "compromised", but you can only trust such systems as much as you trust people selling them. Regarding that Purism thing, I wouldn't trust them more than I would any other laptop. Their FAQ states: Purism ...


21

Hardware crypto modules like this are regulated by a set of standards called FIPS 140-2 which specify the ridiculous lengths that the devices must go to in order to protect the private keys inside them. There are four levels of FIPS 140-2, briefly summarized as: Level 1: It does basic crypto-y things. Level 2: "Tamper-evident"; it's impossible to extract ...


20

Of course, the hardware/firmware also plays as role. The point is at the end of day, firmware also runs programs, and some controllers even provide full computing environments similar to small computers. It is then no small wonder there are projects that revolve around avoiding proprietary formats, either in binary blobs or in proprietary operating systems ...


18

There are mechanisms that could result in data remanence in DRAM beyond the charge stored in the gates (which is typically gone in seconds, especially at normal elevated operating temperature). One is movement of ionic contaminants which can cause slight shifts in thresholds. This could be the 'burn in' that Tom's answer refers to. There may not be any ...


17

It is not reasonable to ever assume data you receive (including your operating system, BTW) from an outside source can be made 100% secure. The most secure way to transfer something and all-but-guarantee no side-effects (e.g. the OS mounting an external drive) is to type in all the data by hand while you be sure you understand it all. Even then you still ...


16

Without more context it's not completely clear, but combined with the line above ("stealing equipment", not "...storage devices/computers") they could be referring to simple theft. This was an issue a few years ago when RAM prices were high - it's very portable. Alternatively DOS-by-theft could be an issue. The same slide refers to "Cutting a fibre ...


15

Do binary blobs pose a potential security threat? In short: yes. Binary blobs are by definition not auditable (barring extended reverse-engineering). You don't know exactly what they do, and whether they have backdoors. One particular binary blob I'd like to highlight is the one in the Intel Management Engine (and the AMD equivalent, the Platform Security ...


12

It is impossible to achieve what you are asking for. You've specified in your criteria that Alan's computer can be pre-infected with arbitrary and unknown malware. In other words, Alan's computer is free to do anything it likes, using any of the hardware under its control. You've also specified that you want a method which is "100%" secure, and you didn't ...


11

You don't need any other device, just a suitable GPU, and a software. For example, cRARk can use your GPU to brute-force rar passwords. And oclhashcat can use your GPU to brute-force lots of things. Why GPU's are much more faster than CPU in cracking? Because cracking is something you can run in parallel (You can use every single core for trying different ...


11

Removing RAM may force a system to swap more so maybe there's a small but higher chance that sensitive information that is stored in RAM is written to a hard drive where it is much easier to recover.


10

Yes. In 2013, researchers uncovered malware that resides in systems' BIOS: http://arstechnica.com/security/2013/10/meet-badbios-the-mysterious-mac-and-pc-malware-that-jumps-airgaps/ In 2015, Kaspersky Labs uncovered malware that resides in hard drive firmware: https://blog.kaspersky.com/equation-hdd-malware/7623/


9

There is a TI wiki page for the Crypto hardware on the AM335x here. On that page there is a tutorial on how to compare the performance of the hardware accelerator versus the pure software implementation. After the modules are installed, OpenSSL commands may be executed which take advantage of the hardware accelerators through the OCF-Linux driver. The ...


9

Yes, it is possible, but that's already clear by now, isn't it. For instance, a hobbyist like me can implement a microcontroller-based hardware keylogger featuring a SIM card to report back via SMS or 3G wireless (similar to Amazon Whispernet). This sort of gadget must be standard issue for spying agencies around the globe, monitoring targets wirelessly. ...


8

Tom Leek seems quite prescient. It is now late 2015 and researchers have shone a spotlight on the Western Digital My Passport and My Book series in a paper titled: got HW crypto? On the (in)security of a Self-Encrypting Drive series This post to the Full Disclosure Mailing List holds the details: http://seclists.org/fulldisclosure/2015/Oct/79 From my ...


8

Several motherboards have overheating protection, if the computer or especially the CPU / graphics card gets too hot, the computer will switch off. So ... turn up the heat in the room (with a big heat-source) until the computer starts rebooting indefinetly. It will be hard not to damage other components I think. In order not to target other nearby ...


8

Binary blobs are code that you have to send to a device to make it work, but that you can't inspect or modify. They are more of a threat to your legal freedoms than your privacy. In the case of Intel chips, you can't write a free-software BIOS, because it must include the non-free binary blobs. Binary blobs let chips outsource storage of code to software. ...


7

In many HSM, there is very little capacity for safe storage (say, a few kilobytes). Therefore, what the HSM really stores in its entrails is some master key K (symmetric). The key pairs that applications use are stored externally, but encrypted with K; they get decrypted and used only within the HSM. In such a setup, keys are both "logically" inside the HSM, ...


7

Since the question doesn't specify what sort of computer system Alan has, I will assume for the purposes of this answer that it's not a typical desktop PC, but instead some form of embedded/project computer system. So, Bob burns the data onto a ROM chip and sends it to Alan via "sneakernet". Alan plugs the ROM chip into his computer. Since it's a ROM, ...


7

No, you are most certainly not the victim of Van Eck phreaking. You know when you feel a bit sick, and you do some googeling and even though you are not a doctor you are suddenly convinced your sympthoms exactly match those of some obscure form of cancer? Then when you tell your doctor he or she sighs and say, no, your not having cancer. Yeah, that is what ...


7

Basically NAND mirroring means that they're opening the phone up, de-soldering the memory chip, copying it off (the "mirroring" bit) and then they either solder it back into the phone, or more likely into a socket in phone that's been deconstructed into a test harness. This way they can try to brute force the PIN to their hearts delight, and if they run ...



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