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12

No. Litecoin uses an algorithm called scrypt which has variables that determine the amount of CPU/RAM required to compute hash. Litecoin's scrypt parameters are fixed at N = 1024; p = 1; r = 1. (http://cryptocur.com/litecoin/) Users of Scypt for password hashing purposes should have the parameters set much, much higher which will put password cracking out ...


12

A USB device with "manipulated firmware" can sure do evil things. For an extreme case, see this answer: the USB device may tell to the OS "hey, I am the FireWire-to-USB converter X.Y, please download my driver from your vendor, then grant me full DMA access when I say so". Though theoretical yet, this is not science-fiction, and it sure is scary. For more ...


11

Given a sufficiently smart adversary with significant resources, you can't. There are five potential attack vectors: Malware on the disk within a partition. Malware within the boot sector. Malformed partition or filesystem structures that exploit bugs in your OS (example) Malware within disk firmware. Modified hardware (e.g. replace the firmware PROM with ...


7

for example, if my laptop is stolen and my house is exploded I suggest that the initial test run involve renting a safe deposit box at a nearby bank to do your offsite backup storage in. This is probably the best answer as well. If you want to get fancy, get a larger safe deposit box and pack the HD in an anti-static bag, then in a small layer of ...


7

Theoretically, to ascertain what a chip does, you break it apart and reverse-engineer it. In practice, this will be nigh impossible to do. Actually, even for software, for which you have the actual source code, you cannot guarantee that the code really always does what you believe it does (otherwise we would be able to produce bug-free code). This is not a ...


6

Wikipedia is correct: on SD cards, you have to trust the host system (whatever the card is plugged in to) to honor the physical write protect switch. Here is the relevant text from the publicly available specification documents. Emphasis is mine. SD Specifications Part 1 Physical Layer Simplified Specification Version 4.10 January 22, ...


6

The AES instructions have to produce the proper output. If they were tampered with in a way that changed output, it would be detected very quickly, and there have been no reports of that. This limits the scope of tampering considerably (to side channels and such), and I can't see that being readily exploitable by the NSA. A random number generator is a ...


5

There is no way circumvent a malicious CPU. Malware can run at different layers on modern compute systems. From top to bottom; Application level, user-mode, kernel-mode, boot-sector, firmware and finally microcode. To understand the true significance of these levels, a layperson would first need to understand the process which occurs every time their ...


5

From a security perspective, you can achieve the same security either through a review of the component (which you want to achieve with an open-source baseband through the many-eyes-principle), or proper isolation. Open source The first appproach is very hard, as regulatory authorities need to certify your baseband firmware. Because of this certification ...


4

The raspberry pi runs on the ARM1176JZF-S processor. ARM is used in more devices than just the Rpi. ARM exploitation is certainly possible. Have a look at the following papers: A Short Guide on ARM Exploitation Effective and efficient bufferoverflow protection Return Oriented Programming for the ARM Architecture Also have a look at this Defcon 18 ...


4

BIOS Most memory chips I've worked with have a W or R/W pin which selects the write mode. Physically tying that one to appropriate logical level should do the trick. Write-protected USB drives I'm a bit suspicious about this one. I've implemented microcontroller<->SD card interface, and the "write-protect" bit is handled completely in software, so you ...


4

I did a talk at Blackhat a few years ago (actually 10 now) that revisited Trusting Trust: http://www.blackhat.com/presentations/bh-usa-04/bh-us-04-maynor.pdf I followed up with an article written for Linux Journal in 2005: http://www.linuxjournal.com/article/7839 I've been researching this topic for almost 15 years now and I can tell you the takeaway from ...


4

Non-executable memory regions are an example of a hardware-based countermeasure: the non-executability of the memory is enforced by the memory management unit. Heap overflow protection can also be implemented at the hardware level (by placing non-readable memory pages at the ends of a heap allocation), but usually isn't, because it greatly reduces the ...


4

You are asking the wrong question. EMP and "magnetic stuff" is not your true concern. First, "EMP/magnetic stuff" will not wipe your harddisks, unless something really unexpected happens, such as a nuclear bomb going off in the stratosphere (and that will likely destroy the circuits, but not likely wipe the platters), or you putting the harddisk onto an ...


4

No, doesn't seem to be anything. Understandable: there is almost zero consumer demand for such a product and it would be very expensive to develop (because of the expensive certification you need from Telecom regulatory authorities). By the way, you're probably worrying about the wrong thing. The main concern with baseband processors is not that the ...


4

The AES competition received 15 candidates, two of which suffered from "academic breaks" (weaknesses that are only theoretical, but still demonstrate that the underlying block cipher is not "optimally secure"). The remaining 13 are, to my knowledge, still unbroken to this day. Therefore, the choice of Rijndael had to be done for reasons other than security. ...


4

The microcontroller (a really tiny computer) in the HSM prevents it - your computer (or whatever device is talking to the HSM) can't directly interact with the memory chip that holds the keys, it has to go through the microcontroller which will allow you to do some operations using the keys (that microcontroller will do the operation and just give you the ...


3

Just to make things clear. Seems to me like there's two distinct questions here: "Do I have to trust my manufacturer?" and "Can a TPM be malicious?". Here's some comments about the second one: A TPM just can't do those kind of things, it's a passive/dumb device. It is typically connected via a standard bus (LPC) that doesn't have access to PCI device or ...


3

For one-way communication you have three classes of issues to contend with: Confidentiality: you want the messages to be unreadable by eavesdropper. Only the receiver (and possibly the sender) should be able to read the message. Integrity and authenticity: you want the receiver to make sure that what it receives is indeed what the authentic sender sent. ...


3

As a rule, you don't. You can't. But you might be able to improve your chances. But what know that instances where hard drives or computers or other devices get "bugged" by adversaries is that these attacks are personal. Either the attacker wants you or your company or your family member or your friend or your neighbor or some other person somehow ...


3

As VMWare workstation provides USB Passthrough, it should be fine using USB wireless cards and doing testing from a kali/linux Virtual Machine. I say should as there's always a risk of bugs in how VMWare passes the data through to the guest VM, so it could have an impact in some circumstances. That said, my experience of VMWare Workstation and using USB ...


3

It is possible to achieve an "instant password change" with an encrypted disk. The idea is that the disk is really encrypted with an internal secret key K. K is a fat, random key that you never see; it was generated when the disk was first powered, and it never changes. K is then stored in a specific slot, encrypted with a second key K', which is derived ...


3

It's not Android[1] but I'm really excited about the Neo900. I loved my old Nokia N900 and thought it was years ahead of it's time. The Neo900 upgrades the internals with fully open source software and hardware. They don't have open source base band firmware but they do specifically address that in their FAQs. I suspect that's as close as you can get. ...


3

In theory, no. The outer shell is a Faraday Cage, so the radiation from the microwave will not penetrate the shell to do anything to the plates. But it will render most of the control board unusable. The radiation can damage the controller chips, and arcing can damage the board tracks and passive components. But swapping the control board could make the ...


3

The name of $TxfLog.blf is self-explanatory: The extension blf indicates a CLFS log file, and TxF stands for Transactional NTFS. You can see that TxF is just a temporary file that backs up transactions to help against sudden crashes, just like similar precautions in modern databases. There can exist some leakage from this file, but it only would consist of ...


3

You are somehow thinking that dead tree docs are less secure than digital copies. I may venture to say you are mistaken in this belief. Digital data may be stolen in a myriad different ways. The scanner may be reporting to HP or other companies/agencies, while your computer may be already compromised. Your computer will have vestigial data on the hard ...


3

Is it common for scanners to somehow cache or log documents they scan (on the scanner machine itself)? Yes, probably nearly all which aren't specially designed to be hightly confidential Does scanner driver/software often have temporary folders which end up leaving a trace of the document? Yes also. Can a networked scanner maliciously or ...


3

Many copy machines and all-in-one scan/print/copy/fax machines (especially from HP) have internal hard drives they use for temporary storage. It's been in the news from time to time that people have recovered sensitive data from these drives, either using data-recovery software or by simply reading the drive filesystem.


2

You might be interested in this talk that was given at DEFCON a few years back. Summary: if you are using WPA2, a separate key is used to encrypt broadcast traffic vs. unicast traffic. So in that sense, connections are isolated from each other. HOWEVER, you're still vulnerable to an insider attack; a malicious client could spoof ARP and intercept traffic ...


2

Presumably it doesn't decrypt the drive just changes the password to one the drive knows internally (probably blank). I.e. the actual data on the disk platters is encrypted regardless of whether a password is set, but the key which it is encrypted with is not. I have no specific knowledge of how WD Passport encryption - I am just noting that the instant ...



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