Securing Linux systems and applications; understanding Linux security features.

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3
votes
1answer
97 views

Is installing Debian package safe?

If I understand correctly, the maintainer scripts in Debian packages are executed with root privileges. I assume that this means that, contrary to my expectation, installing a malicious package can ...
4
votes
1answer
212 views

Decryption using GRUB and TPM

I'm trying to plan security routine for my new Linux install and few questions came up during searching for solution which meet my needs. Is it possible to use private key from TPM in GRUB to ...
16
votes
8answers
1k views

Is it possible to prevent a file type from being determined in a Linux system?

I have several files on my Ubuntu system, which are LUKS encrypted partitions. For my own shame up to this day I thought that simply changing binary file's extension will be enough to hide what a file ...
1
vote
3answers
100 views

Protecting Uploaded Confidential Files [closed]

We have a web application in Linux (App A) using PHP and Zend and another in Windows using Asp.net C# (App B). They both access the same database. App B is for internal use only while App A can be ...
1
vote
1answer
101 views

Securely hide a directory from the OS using java?

I have a project to do for my master's degree and I need to do a Java app which loads a file (read some attributes and copy the file to a working directory), basically any file, and make the working ...
1
vote
2answers
63 views

Detect SSH InBound / Oubound Connections

I'm noodling with the idea of managing SSH connections on Linux server using a program (not sure what it will be written in yet) that monitors inbound and outbound connections. Is there a way to ...
2
votes
1answer
56 views

Is it possible to use obtained wildcard certificate on more than one server?

We are using two Debian servers in our company (with apache 2 as httpd) and our services are split between those two of them. One server has the website, the other has some minor sites under ...
-4
votes
1answer
2k views

Kali Linux Veil-Evasion install problem [closed]

I can't install Veil-Evasion. I have this error: Installing (Wine) i386 Binaries Reading package lists... Building dependency tree... Reading state information... Package wine-bin:i386 is ...
17
votes
3answers
946 views

ISO27001 and Linux/Ubuntu

My company has an ISO 27001 certification. They provided me a new laptop with Windows 8 OS in it. I asked if I can have a Linux/Ubuntu OS installed, they said that it is not possible due to the ISO ...
2
votes
0answers
144 views

Why use oddly compiled ELF files for Linux malware?

I ran file on some Linux malware ELF files that I've acquired over the last couple of years. I noticed some oddities: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), statically linked, for ...
2
votes
2answers
164 views

Is writing to /dev/null secure?

I am working on a web-service based crypto project in JAVA. The basic idea is for the client to send a SOAP request to a servlet to encrypt data. For data transmission I am using MIME/data-handlers ...
3
votes
1answer
169 views

Anti-live forensic programs

Against dead forensics acquisition we can use disk encryption (we can use TrueCrypt for example). I was wondering do software exists against live forensic ? Can you give me a list for windows and ...
1
vote
0answers
282 views

Volatility Framework 2.4 - No suitable address space mapping found [closed]

I made some dumps with different formats (.DMP and some file made by LiveKD utility) in Windows 8.1 x64 OS. The first one is a explorer.exe dump file which was created by TaskManager->Create Dump File ...
1
vote
1answer
95 views

Strange SECCOMP entries for sshd in audit log

I've posted this over at ServerFault but haven't received a response over there. I'm not a security professional, but I'm curious as to what kind of attack this might be and how the attackers might be ...
2
votes
1answer
261 views

Dump linux password in clear text

Is it possible to dump a Linux password in clear text format? In Windows it is possible to do so using "Windows Credential Editor".
1
vote
1answer
62 views

RDRAND in Intel Celeron CPUs under Linux

Is there any reason to believe that the hardware RNG in an Intel Celeron CPU is more unreliable than in other CPUs? Can someone confirm that what Linus Torvalds says is true, namely that Linux does ...
0
votes
0answers
102 views

How 'private' is my setup?

I'm currently running QubesOS (so essentially a virtualized Fedora operating system), which I use to access an offshore VPS through I2P (using garliccat). I then route all my traffic through the VPS ...
3
votes
2answers
146 views

How to overwrite ebp on stack alignment?

I want to exploit a simple program #include <stdio.h> #include <string.h> int main(int argc, char** argv) { char buf[128]; strcpy(buf, argv[1]); return 0; } The disassembly ...
0
votes
0answers
19 views

At OpenSSH ssh server side key files has 0 data. I would like to know the reason for it

I am using the Monta Vista Linux. In this recently i have observed the ssh keys files has 0 data due to which the keys were not generating and i am not able to login to machine via ssh because of key ...
4
votes
1answer
130 views

Desktop Flickers Past Lock Screen

I'm using Fedora 22 with Gnome 3. I have a password set for my user account, so when my laptop awakens from sleep, I am presented with the lock screen and must enter my password before getting to my ...
6
votes
2answers
260 views

Does the new Fedora package manager allow unauthorized installations?

I just upgraded to Fedora 22. The biggest change from the previous version is that the yum package manager is now replaced with dnf. One change I've noticed is that if you try to execute a command ...
2
votes
2answers
60 views

Are there any dangers in sharing ifconfig information publicly?

If I were to share my ifconfig information from Linux publicly, is there any possible danger associated with this action?
-5
votes
1answer
445 views

How to use wordlist [closed]

I have downloaded a wordlist from https://crackstation.net/buy-crackstation-wordlist-password-cracking-dictionary.htm The size of the wordlist is 4.2 GiB (compressed) or 15 GiB (uncompressed) The ...
5
votes
5answers
992 views

How secure is it to keep the salt with the password hash? [duplicate]

In Linux we have the salt just next to the password hash in the /etc/shadows file. I always hear that salt value prevents hashed passwords from being cracked by brute force methods. But if somehow we ...
5
votes
1answer
141 views

Video site requests Adblocker to be shut off, next day I have 3 “weird” bookmarks

I was on a site trying to view a video and the site requested that I turn off my adblocker to view the video. So I did and then the next day I noticed that I had 3 "weird" bookmarks in my bookmark ...
0
votes
2answers
290 views

How to make data in hard disk unrecoverable on linux [duplicate]

I need to wipe completely the data on my hard disk so it's unrecoverable. I'm actually using Linux, i have seen this command on the web, but I don't know if its secure. shred -zvn 35 /dev/sdb
0
votes
1answer
94 views

When can the exploit for CVE: 2006-7098 be used?

I'm studying the vulnerabilities of an old version of Apache, the 1.3.34. And I don't quite understand in what exact situation the CVE 2006-7098 vulnerability can be exploited. The README included in ...
4
votes
1answer
134 views

Can BTRFS provide authentication on an encrypted disk?

One of the problems of disk encryption is providing authentication. An attacker with access to the ciphertext can modify the ciphertext at will without consequence. Given, this isn't a likely attack, ...
0
votes
0answers
214 views

TPM Command Line Tools

I am trying to create a key storage hierarchy on TPM (Trusted Platform Module) on Linux (CentOS 6.4). The most commonly recommended TPM tool suite on Linux is TrouSerS. However, the command line suite ...
0
votes
2answers
131 views

PCI-DSS, what is the best distro? [closed]

What is the best distro of Linux to get PCI-DSS compliant? I am using Debian 8 because I think Debian is one of the most stable versions, but it seems not to be enough, I am struggling with a lot of ...
5
votes
1answer
641 views

Why is plain dm-crypt only recommended for experts?

I am curious about the following claim from the Cryptsetup FAQ: 2.4 What is the difference between "plain" and LUKS format? First, unless you happen to understand the cryptographic background ...
0
votes
2answers
365 views

Can I VPN a phone's connection to my home network, and then apply my home firewall to my phones network connections?

I have a decent firewall/router at home, and I was wondering whether it would be possible to use my home firewall for the connections that my phone makes, even when I'm not at home. It would mean ...
1
vote
2answers
78 views

How to use Aircrack-ng when knowing part of the password?

Let's say I know the password starts with "1234" and after that there is a commonly used password. I would like to use the word list I have for the second part of the password, but to include somehow ...
2
votes
2answers
43 views

Which software RNG for linux?

A headless server can suffer from a lack of entropy, which is a problem given that encryption needs random numbers. In the absence of a hardware random number generator (RNG) the numbers must be ...
5
votes
2answers
86 views

SSH: Security of Pubkey Authentication vs Password

Why is Pubkey Authentication considered more secure than a password, and does this apply to my situation (described in more detail below)? I'm a scientist (no formal IT training), but I built and ...
3
votes
1answer
109 views

Is a newly installed server with no services running (but connected to the web) at risk?

A new server has just been installed but literally has nothing else running on it, no services setup to SSH in or anything yet (it's a Linux server). However, it is hooked up to the web so I can ...
0
votes
1answer
129 views

Server full disk encryption protection from malware

A group of LINUX servers is using dm-crypt to encrypt data. The servers do not store data long-term but are only temporary stopping points for data before it is sent to other systems. The time the ...
2
votes
0answers
102 views

chroot ssh users [closed]

I am using CentOS 7. I need to give shell access to ssh users but restrict them in a jail. I have used jailkit to set up the jail. I have copied all necessary libraries, binaries that are needed for ...
1
vote
1answer
57 views

Linux Kernel module signing

If the linux kernel is compiled to check for kernel modules signing, it checks the validity of the public key (X.509) w.r.t the current system time. For the first time the system is booting up, it ...
4
votes
1answer
129 views

How can I delete a password and lock the account in one step?

I have a minimal server install on a remote machine with a root password set to a temporary, but chosen, value. I have added a separate administrator user. This user has an authorized key for SSH, no ...
1
vote
0answers
92 views

Linux: Chinese Unionpay plugin, Ubuntu 64-bit - Spamware / Trojan?

China / Linux / Bank / Trojan / Backdoor / Executables Hey guys. I've got an account with a Chinese bank (I live here), and in the process of setting up an online account for the Chinese version of ...
5
votes
1answer
345 views

/dev/random in EC2 cloud

is /dev/random any good in AWS EC2 for use in making a shared key that will be passed over a secure channel? i am concerned that a launched instance would have not much entropy to begin with. what ...
38
votes
9answers
6k views

Is full disk encryption on a server in a secure data center pointless?

I am having a debate with several people regarding how much protection full disk encryption provides. dm-crypt is being used to encrypt data which is required by my company to be encrypted at rest. ...
0
votes
2answers
115 views

How hard would it be to scramble crypto keys in memory on command?

I'm looking for a way locate a set of keys in memory on command. Use case would be cold boot attack prevention: a trigger on rack open, scramble the keys in memory followed by shutdown in full disk ...
-1
votes
1answer
290 views

Can I use a VPN to disguise internet traffic at work? [closed]

I have seen this question asked before; I want to know if I can use a VPN to disguise my internet traffic so my employer can't see what websites I'm visiting while at work. However, unlike most ...
2
votes
1answer
464 views

Are there any security implications in creating an SSH key for the root user?

I've written an install script on a server to quickly set up new sites in the /srv directory. It needs to do a git clone, and has to be run via sudo in order to have the permissions to do all the ...
4
votes
1answer
282 views

What does a signed Linux kernel image get me?

On Ubuntu and possibly Debian systems, you can install packages which contain images which are signed by Ubuntu's EFI key. For example, linux-signed-image-generic-lts-trusty is one of these packages. ...
3
votes
3answers
628 views

Error message in Apache logs shows /bin/bash and wget

I am wondering if my server is compromised or not I just looked at my log and seen the following line in there [Thu May 14 09:10:42.587255 2015] [autoindex:error] [pid 3422] [client ...
1
vote
2answers
245 views

Code Vulnerability in Shell script

I was given an assignment for my Computer Security class. We we were given a piece of code to analyze and determine the vulnerabilities that it might have. #!/bin/sh # shell script to create a copy ...
0
votes
1answer
267 views

Moving /tmp to an encrypted tmpfs

BLUF: I'm using an SSD on my system, so my primary reason to use tmpfs to increase the life of my drive by moving high read/write files to volatile memory. But from a security point of view, I'd also ...