Computer memory refers to a physical device that is used to store sequences of instructions (programs) or data (program state information) on a temporary or permanent basis for use in a computer.

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Why are buffer overflows executed in the direction they are?

I'm following The Security Tube’s video here. He overviews buffer overflows, and mentions how memory is executed from highest to lowest in the stack (at least with his implementation I assume). So we ...
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13answers
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Are passwords stored in memory safe?

I just realized that, in any language, when you save a password in a variable, it is stored as plain text in the memory. I think the OS does its job and forbids processes from accessing each other's ...
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Recover the prior contents of RAM from a turned-off PC?

I've heard that if your PC is turned off, then an attacker can recover the RAM from the last session. I find this hard to believe. How could it be done?
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environment variable accessibility in Linux

Perhaps this is a trivial question, but how accessible are environment variables in Linux between different users? e.g. if Alice executes export FAVORITE_FOOD=`cat /home/alice/fav_food.txt` Can ...
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4answers
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OS with encrypted RAM?

Are there any applications, JIT frameworks or operating systems that focus on encrypted virtual memory, or perhaps virtual machines that do something similar? I know there are processors (albeit old, ...
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2answers
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Safely disable firewire/thunderbolt, patching up DMA exposure

I understand that Firewire 400/800 and Thunderbolt have DMA enabled, and a malicious hardware device can easily read and manipulate system memory at will. If I disable the software drivers for these ...
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3answers
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SSD (Flash Memory) security when data is encrypted in place

I'm surveying current techniques on flash memory security. I've learned that the non-in-place update of flash memories prevent us from adapting the same encryption techniques that we used on hard ...
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6answers
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Can RAM retain data after removal?

Is it possible for RAM to retain any data after power is removed? I don't mean within a few minutes such as cold boot Attacks but rather 24 hours plus. Working with classified systems the policy ...
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How can the impact of cold boot attacks be minimized?

Short of powering down and maintaining physical security for sufficient time, what are effective strategies for keeping keys from being disclosed by cold-boot attacks, and can anything be done without ...
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1answer
458 views

Are encryption keys wiped from RAM before hibernate, or how to do it (Luks and Truecrypt)

Using Linux, I have system and swap/hibernation partitions encrypted with LUKS, and data partitions encrypted with Truecrypt, and I am wondering when I put my laptop to hibernation if the encryption ...
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3answers
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Why does printf() vulnerability require 4-bytes of junk data? - “Hacking: The Art of Exploitation”

I've been reading "Hacking: The Art of Exploitation 2nd Ed." and I hit a part that's not explained clearly enough for me. In the section "Writing to an Arbitrary Address" Jon Erickson creates a ...
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4answers
825 views

Why don't computers check whether there are memory contents in some memory space?

Buffer overflow occurs because it writes to memory spaces that are used by, or will be used by other parts of the program. Computer programs usually write to the memorylocation that has been ...
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1answer
161 views

How long would a computer have to be off to be resistant to a cold boot attack?

I understand that the longer a computer is off, the more resistant it is to a cold boot attack. I also understand that an AES key can be reconstructed from a redundant round key schedule even after a ...
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Memory Dumping - Cause for concern in Virtualization?

Recently, I started exploring threats to Virtual machines in general. The first question that popped into my head was whether a host machine can dump its entire memory onto a file, and inspect the ...
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1answer
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iPhone 5/6 RAM security

I'm interested in how the RAM can be exploited in iPhone 5+, iOS 8+. I've previously discussed general iPhone encryption and from the response it reads: There are many exploits over the years ...
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2answers
535 views

Are there volatile memory chips which dont retain data after power off?

It was demonstrated that dram modules can retain information up to 10 min after power off in certain conditions. My question - are there memory types which will retain data 10 sec at max even if being ...
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1answer
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Effects of DDoS attacks on memory use under Linux

Can someone whose Linux system is under DDoS attacks give me exact data on the effects of the Low Orbit Ion Cannon (LOIC), the High Orbit Ion Cannon (HOIC), Slowloris, PyLoris, Hping etc. on memory ...
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2answers
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Protection of Keys/Passwords on Virtual Hardware (XEN, KVM, VMWare, etc.)

Is there any reasonable way to secure data on virtual hardware? What I mean by "virtual hardware" is the various hosted systems that one can rent from various online hosters, that run on top of XEN, ...
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5answers
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What is the benefit with using encrypted RAM Memory?

I sometimes hear that encryption is used for the RAM Memory, but I don't really understand why this is needed. Why is RAM Memory needed to be encrypted? and is this done by the hardware, the ...
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1answer
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Why are some DLLs not randomized? What makes it hard to deploy full ASLR for all DLLs?

One of the challenges with deploying ASLR for everything is that, at least on Windows, some DLLs (libraries) are not compiled in a way that's compatible with ASLR. (They're not compiled as position-...
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1answer
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Stack buffer overflow confusion

I am trying to dig deeper into the nuts and bolts a stack buffer overflow using the classical NOP-sled technique. Reading some articles and watching videos brought me to a confusion which can be ...
10
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2answers
367 views

How to know whether a RAM module is vulnerable to rowhammer before buying?

I'd like to know (or at least perform some reasonable guess) if a RAM is vulnerable to rowhammer attack. I haven't found any list of vulnerable or secure RAM modules. I've seen some general rules (...
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3answers
478 views

An OS that does not trust its RAM?

I wonder if it is possible to write a kernel that would keep all of its RAM encrypted, storing the key in the CPU cache, so that the machine would be resistant to cold-boot attacks?
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0answers
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security of libgcrypt when cross-compiling for windows?

Looking at libgcrypt, specifically secmem.c it seems that it does not account for windows-specific memory handling (e.g. VirtualLock) and in fact there is a very troubling comment: #elif defined (...
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2answers
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Can unencrypted keys & logins be kept out of program memory?

No matter what technique is used to store encryption keys & logins, it seems that all roads lead back to program memory (as far as I know), as an unencrypted version of the keys & logins will ...