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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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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6answers
1k views

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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4answers
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Why encrypt data in memory?

I saw that KeePass not only encrypts its password-database-file, it also can encrypt the passwords it holds in memory. This is just an example. I thinking of a new project dealing with sensitve / ...
12
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4answers
5k views

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, ...
12
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2answers
883 views

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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4answers
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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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5answers
3k views

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 ...
10
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1answer
681 views

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 ...
10
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1answer
2k views

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 ...
9
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4answers
2k views

How does System Memory Dump work?

So there are so many pen-testing tools that perform a memory dump on the system. How exactly do they work - what exactly happens ?
9
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1answer
2k views

How to properly delete all data from cell phones?

Lately I've been thinking to get rid of some old smartphones; among them an Android device and a Blackberry. Not selling or recycling them is the ideal solution, however, I still would like to know ...
8
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4answers
595 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 ...
7
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2answers
534 views

How can I detect (or inventory) all DLLs that don't use ASLR?

Based on this IE zero day, I'm interested in listing all DLLs in our systems that have been compiled to not work with ASLR. Ideally, I'd like to analyze a static file and not load it into memory to ...
6
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6answers
862 views

Implications of securing data in RAM

Someone told me that his company is storing all application data (at least the sensitive data I guess) in RAM for security. Their application runs for long periods of time, so data stays in memory for ...
6
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3answers
4k views

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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3answers
2k views

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 ...
6
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1answer
182 views

Do 64-bit applications have any security merits over 32-bit applications?

A particular article from arstechnica.com stated this. One of these protective measures is called Address Space Layout Randomization, ASLR, and it works by moving DLLs and application memory into ...
6
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2answers
3k views

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 ...
5
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3answers
311 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?
5
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2answers
201 views

Why did it take so long to enforce memory permissions?

From the Wikipedia page on DEP. DEP was introduced on Linux in 2004 (kernel 2.6.8[2]), on Windows in 2004 with Windows XP Service Pack 2,[3] while Apple introduced DEP when they moved to x86 in ...
5
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3answers
414 views

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 ...
5
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2answers
985 views

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 ...
5
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1answer
3k views

Protect access to an SD card

How can I protect access to an SD card, so that only authorized users can read or modify the content of the SD card. Currently everybody who has physical access to the SD card can read or modify ...
4
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2answers
408 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 ...
4
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3answers
161 views

Is there a common name for a software defect that leads to unexpected transfer of secret over the wire?

Suppose in a C++ program I use a memory region for temporarily storing an encryption key and don't overwrite that region afterwards. Then my program wants to send a data packet over the network. Due ...
4
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2answers
467 views

Smashing the stack if it grows upwards

As we know that on most of the processor architectures, the stack grows downwards. Hence, memory exploits involving smashing of stack and buffer overflow and their explanation make sense. Just ...
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4answers
4k views

How to make / dump contents of memory for forensics analysis?

I work as a Information Security analyst and was recently tasked to look into Incident response + computer forensics related topics. For starters, I am experimenting on my PC which is running Windows ...
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4answers
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Detecting or preventing process memory injections on Windows (anti-hack)

Standard hacking case. Hack injects into a started game process and writes over process memory using WriteProcessMemory call. The situation is like this: we are hosting a game server clients join ...
4
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1answer
62 views

Principles of memory forensics tools

I am currently writing a thesis about digital forensics which includes a chapter about memory forensics. Besides the tools and the methods of acquiring various data with them, I am kind of desperate ...
4
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1answer
85 views

What does EMET do for Windows 8.1?

I recall seeing, upon release of Windows 8 a while ago that a number of new mitigations and memory protections had been put in place but i'm unsure if these are the same protections offered by EMET. ...
4
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1answer
337 views

What attacks does a W^X policy prevent against?

Write xor Execute (W^X) is a policy that a block (page) of memory cannot be marked as both writeable and executable at the same time. What attacks does W^X prevent, with and without the following: ...
4
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1answer
315 views

A simple example for showing the use of Data Execution Prevention (DEP) security feature

I am finding it really hard to figure out why we need a DEP! Microsoft states this about DEP: The primary benefit of DEP is to help prevent code execution from data pages. Typically, code ...
4
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1answer
176 views

Does Linux kernel use DEP for kernel memory?

Does the Linux kernel use DEP internally for its kernel memory? In other words, does the Linux kernel take care to ensure that, when the kernel is executing (in kernel mode), every executable ...
4
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1answer
424 views

How dangerous is a virus introduced to a malicious website in chrome?

I am using Google's Chrome browser under Linux (Ubuntu) 64 bit for web browsing. If I a virus uses for example a leak in the flash player, the virus will get the privileges of the user who started ...
3
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1answer
464 views

Is Enabling DEP (Data Execution Prevention) For All Programs Worth the Risks?

Data Execution Prevention in Windows supposedly is a line of defense against malicious code by "by monitoring your programs to make sure that they use computer memory safely". However, I also know ...
3
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2answers
321 views

Does a flatbed scanner remember any of its previous scans?

I'm about to get rid of an older scanner and I want to make sure that no one is able to acquire any sensitive information that was scanned previously with the machine. I assume it does have some kind ...
3
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2answers
425 views

Possible trojan/virus in memory?

I've extracted objects (JPEGs) from processes` memory dumps (obtained with memdump command from volatility framework) and got strange results after searching the memory pages of the main thread of ...
3
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2answers
108 views

Crypto software: overwrite sensitive buffer

Is it common to implement crypto software in such a way that sensitive buffers are overwritten before free'ing memory? For example when they contain a private key or the plaintext message.
3
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1answer
180 views

how does a return to system allow an attacker to evade a non-executable stack?

I am learning about return to system call attacks for a security class. I understand that in this kind of attack, attackers replace the standard return value for a stack frame with the address of a ...
3
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1answer
116 views

How can one gain additional privileges from being able to read kernel memory?

Given the ability to read (but not write) arbitrary kernel memory as an unprivileged user, what approaches might one take to gain additional privileges on the system? Ignoring the 'trivial' method of ...
3
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1answer
533 views

Two questions about learning Linux exploit development fundamentals

getting ready to delve into the technical world of vulnerability assessment, and I have two questions about where to find certain information. First, I plan on reading "Understanding the Linux ...
3
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3answers
106 views

C++ memset() memory overflow

I am new to C++. Can any C++ expert tell me would this causing buffer overflow? Sample Code: MyObject op; memset(&op, 0, sizeof(MyObject)); On my view it is ok to be this since the limit is ...
3
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1answer
208 views

File Vault 1 password from memory dump

I have a osx 10.9 machine with a File Vault1 encrypted user partition. I would like to remove the encryption, but I don't remember the "master key" which is the only way to remove encryption ...
3
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1answer
101 views

Exploiting memory corruption issues using a DLL file

I was listening to a talk on Return Oriented Exploitation from the Black Hat 2010 conference. The speaker mentioned something about using the DLLs to exploit some of the memory corruption issues. I ...
3
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3answers
372 views

Protecting against Firewire DMA vulnerabilities in Linux

I know there have been questions on this in the past but they all seem quite outdated, or not that specifically relevant. I need to use a 1394(Firewire) connection, however am concerned with possible ...
2
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5answers
518 views

What should one do when he/she wants to protect him/her home--computer--?

As you know, deleting a file by pressing shift-delete or by using the Trash doesn't mean that the file is unrecoverable. It's data persists on your computer. In day to day life, adversaries use ...
2
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2answers
276 views

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 ...
2
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3answers
213 views

PGP on hibernation files?

I was afraid reading this: This $299 tool is reportedly capable of decrypting BitLocker, PGP, and TrueCrypt disks in real-time. It seems to me that PGP and other sensible tools have to lock memory to ...
2
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3answers
233 views

Resources to learn about memory allocation & security

Are there any good online resources to pick up knowledge about how memory allocations affect security? Its a new area for me, and any pointers on where to get started would be appreciated.
2
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1answer
126 views

US Department of Labor Watering Hole Attack

So I read this article about how the US Department of Labor's website was compromised and users were redirect to a site that installed malware: ...