Hot answers tagged

58

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 ...


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 ...


22

TL:DR - Yes, routers CAN be vulnerable. Misconfigured/Unconfigured routers - A ton of people just install their routers and leave the default accounts turned on without modification. Thus allowing attackers easy access. Vulnerable built in scripts - http://www.reddit.com/r/netsec/comments/1xy9k6/that_new_linksys_worm/ See: What is the ...


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 ...


17

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 ...


13

Other answers have been given to answer whether routers are secure: your router likely has unpatched vulnerabilities. A recommendation for making things more secure would be to put a real Linux box in front of your router. Configure it for automatic security updates every 10-30 minutes so your patches come quickly. For kernel vulnerabilities, you could use ...


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 ...


10

Trusted Platform Modules A Trusted Platform Module (TPM) is a hardware chip on the computer’s motherboard that stores cryptographic keys used for encryption. Many laptop computers include a TPM, but if the system doesn’t include it, it is not feasible to add one. Once enabled, the Trusted Platform Module provides full disk encryption capabilities. It ...


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. ...


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 ...


7

Short answer: That won't work. You'll need to degauss it, which will render the drive unusable. Long answer: Sure. Get a powerful magnet, put it next to the hard drive, with N facing the drive. Then flip it around so S faces the drive. Then flip it again, then again. Do this a few thousand times a second. If you do it any slower or just put it near the ...


6

A router is actually a small computer; most of them use the same kind of software as full-fledged servers (typically some Linux variant). As such, it has security holes, that should be patched promptly when discovered. Vulnerabilities that are not fixed might be exploitable and yield remote control to attackers, at which point they can do what they want with ...


6

In theory any device can store anything, because it is speced to meet an interface, not spec'd for its implementation. Realistically speaking, the answer is more murky. This, by the way, is where SSD's get so interesting because there is no accepted way to tell a SATA SSD to "wipe everything" (edit: no way that is reliably trustworthy, at least) From ...


6

Can SSM reliably prevent buffer overruns? It does not claim to offer 100% prevention but it definitely offers more granular protection compared to previous hardware based solution (which had usually page granularity) and much better performance than software based protections with a similar granularity. There are some limitations like Your code has to ...


6

Well, yes, it's called a switch. Microphones from a hardware perspective are (in the case of electrets, at least) a capacitive component which produces a small current when the membrane moves due to sound. By amplifying this signal you can capture a sound signal. By simply disconnecting the audio line from the mic itself, or just turning off the amplifier ...


5

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 ...



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