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158 votes

Are the sticks of RAM in my desktop computer volatile? Is it safe to sell them?

Yes, they're safe. Consumer memory DIMMs use volatile SDRAM memory. Volatile means that it does not hold its state after you turn it off. SDRAM memory chips are constructed from an array of memory ...
Polynomial's user avatar
  • 135k
110 votes

How to prevent a hosting company from accessing a VM's encryption keys?

You can't, plain and simple. If you don't trust the hosting company, you don't host with them. This is law #3 from 10 immutable law of security: Law #3: If a bad guy has unrestricted physical ...
Lie Ryan's user avatar
  • 31.4k
70 votes

Are the sticks of RAM in my desktop computer volatile? Is it safe to sell them?

Yes, they’re safe to sell. No consumer PCs use non-volatile RAM for their main memory.
Mike Scott's user avatar
  • 10.3k
62 votes

Emergency method to erase all data off a machine within seconds

Thermite. Thermite burns at a temperature of thousands of degrees centigrade, which would be more than sufficient to destroy all the data stored in any modern data storage medium. It is also already ...
nick012000's user avatar
54 votes
Accepted

Emergency method to erase all data off a machine within seconds

There are two DEFCON videos from 2012 and 2015 exploring this exact issue: DEFCON 19: And That's How I Lost My Eye: Exploring Emergency Data Destruction DEFCON 23: And That's How I Lost My Other Eye.....
Slava Knyazev's user avatar
48 votes
Accepted

What is the benefit of having a cryptographically secure hash algorithm in hashmaps?

Sometimes applications use untrusted data as the key in a hash map. A simple implementation can allow the untrusted data to cause a denial of service attack. Hash maps are fast - O(1) - in the best ...
paj28's user avatar
  • 33.4k
44 votes

Emergency method to erase all data off a machine within seconds

If you trust encryption then you could encrypt your entire drive using Linux: LUKS (supported by all major distributions) Windows: BitLocker As soon as you physically switch off the device, all the ...
Artem S. Tashkinov's user avatar
39 votes

What is the benefit of having a cryptographically secure hash algorithm in hashmaps?

Insert, search, and remove operations on hash tables have O(n) worst case behavior. If an attacker can choose keys to be inserted into a hash table and they can compute the hash function themselves ...
Future Security's user avatar
32 votes
Accepted

Is assigning decrypted keys to a variable in application secure?

Yes, it does mean that the key will be stored in the application’s memory. Yes, there is a risk that malware (with sufficient privilege) can read it from there. This risk is hard to avoid — if you ...
Anders's user avatar
  • 65.6k
29 votes

Should crash dumps (e.g. from Breakpad, Windows) be encrypted and signed?

Dumps give too much info for hackers to reverse engineer or hack the software, say to enable features or licenses? The dumps must, at some point, exist in unencrypted form. An attacker with full ...
vidarlo's user avatar
  • 16.5k
29 votes
Accepted

How can two identical no-PIE binaries run simultaneously?

... it always has the same absolute base address. No. Each process is provided by the OS with its own mapping of parts of the systems memory. The addresses in a non-PIE binary are not absolute to the ...
Steffen Ullrich's user avatar
28 votes

Emergency method to erase all data off a machine within seconds

A RAM disk RAM is cool in that it is volatile memory. This essentially means that once power is cut, all data is lost completely and can never be recovered - essentially, this irreversibly and ...
Daniel H.'s user avatar
  • 381
19 votes

Emergency method to erase all data off a machine within seconds

Hard Drive with glass platters HDD’s with glass platters are common. All you need to do is make sure that your data is stored on one of them, and, in an emergency, chuck it at the ground really hard. ...
Daniel B's user avatar
  • 441
18 votes

What is the benefit of having a cryptographically secure hash algorithm in hashmaps?

I agree that's a little vague and it's going to heavily depend on how the hashmaps are used. Here's my guess: say you're taking some input from users, say [Firstname.Lastname] and using that as the ...
Mike Ounsworth's user avatar
16 votes

How to prevent a hosting company from accessing a VM's encryption keys?

so that it would not be economically viable to spend time & resources to get them. I hate to break it to you, but you simply aren't that important. No-one knows you or your web app. So it's ...
Graham's user avatar
  • 621
14 votes

How can you detect kernel exploits?

No, there is nothing all kernel exploits have in common. Or at least, there is nothing unique to them and not present in standard, legal interaction with the kernel (such as using syscalls or ...
forest's user avatar
  • 66.8k
13 votes
Accepted

How does full memory encryption in newer processes protect against DMA attacks?

How does memory encryption impact DMA attacks? Full-memory encryption is not designed to protect against DMA attacks. That is what an IOMMU is for. The IOMMU is configured using a type of ACPI table ...
forest's user avatar
  • 66.8k
13 votes

How to prevent a hosting company from accessing a VM's encryption keys?

In theory, you should be able to use the trusted hardware features of modern CPUs to run your disk encryption, or even your entire VM, inside a tamper-resistant part of the CPU, having all the data on ...
interfect's user avatar
  • 305
13 votes

Emergency method to erase all data off a machine within seconds

The framing of this question is just completely wrong, and I'd go so far as to suggest the question doesn't belong on Security SE but Worldbuilding SE if you're trying to make up a world where it does ...
R.. GitHub STOP HELPING ICE's user avatar
12 votes

Emergency method to erase all data off a machine within seconds

Some of HPE's SmartArray RAID controllers (for instance, the P408i) support transparent disk encryption. One of the supported configuration modes involves keys that are only ever stored in a ...
bta's user avatar
  • 1,121
12 votes
Accepted

In-memory pepper

First: you are definitely correct, it can't be stored alongside your code, no secret should. It obviously needs to be held in memory by the server since it needs to be used. However, it can't be in-...
Marc's user avatar
  • 4,301
10 votes
Accepted

Does Oracle's GuardedString protect sensitive data against heap or memory dumps?

Some deeper look into the actual implementation will help an attacker understand the data structure of a memory dump, and from what I found in EncryptorImpl there has been put no effort into ...
Anton Kaiser's user avatar
10 votes
Accepted

Why is accessing kernel memory a security risk?

In order to understand the threat from Meltdown, you need to understand how memory is organized in modern computers. The naive view of memory is that each memory address corresponds to a specific set ...
Mark's user avatar
  • 34.7k
9 votes

Was TRESOR integrated in the Linux kernel?

No, TRESOR was never integrated into the Linux kernel. It is specific to the x86 architecture, and requires AES-NI in order to not have a pretty nasty overhead. Due to the limited size of DR registers ...
forest's user avatar
  • 66.8k
9 votes
Accepted

How can I protect my home/office computer against row hammer?

The only reliable hardware mitigation that does not involve downgrading to a motherboard with DDR2 is to use memory that supports TRR (Target Row Refresh), which is optional for LPDDR4 (not the same ...
forest's user avatar
  • 66.8k
9 votes
Accepted

Viewing the stack

Getting a dump of memory the simple way You can simply send your vulnerable process a SIGSEGV (kill -SEGV pid) and, if coredump is allowed (ulimit -c unlimited), you gonna get a nice core dump file ...
binarym's user avatar
  • 784
9 votes
Accepted

How can Process Hacker view my password manager's memory without administrative rights?

Per its documentation, Process Hacker actually launches a kernel mode driver, KProcessHacker. A kernel mode driver does have access to all memory. Sources: https://github.com/processhacker2/...
Jesse K's user avatar
  • 1,068
8 votes
Accepted

Why use a passphrase for RSA key?

You do not need a passphrase for your RSA key. But if your key gets compromised (for example, because you carry the key on a thumb drive and you lose it), an attacker could immediately access the ...
Lukas's user avatar
  • 3,178
8 votes
Accepted

How can Windows 10 not have the password in memory?

A quick search turned up the link below. They created a new technology called CredentialGuard, which isolates secrets in virtualized secure environments rather than storing everything in LSA like ...
0rigen's user avatar
  • 96
8 votes
Accepted

Ring 1 and Ring 2 Memory Protection Architecture

The four ring system was designed by Intel for anyone to use, and Microsoft chose a scheme to simplify development work and provide a faster OS at the cost of some security. As far as Microsoft is ...
phyrfox's user avatar
  • 5,724

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