Securing Linux systems and applications; understanding Linux security features.

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1answer
335 views

Installing applications with different user accounts on linux

I have basic question about installing applications on Linux operating system, using the Oracle database as an example. When installing the Oracle database package, I created a user called ora112, a ...
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1answer
687 views

Linux tools to choose suitable Cisco ASA 5500

I have a linux webhosting server which affects a high DDOS. I want to use Cisco ASA 5500 Series Adaptive Security Appliances to protect the linux server from this DDOS. I know there are many factors ...
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5answers
1k views

Can a .sh file be malware?

Can a .sh file be a virus or something harmful? Is it like .exe files on Windows? If yes can someone read this script and tell me if it safe and is it effect any how on gpg security. It gives me an ...
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2answers
2k views

Using TPM with DMcrypt?

Is it possible to use TPM for storage of some private key? It's not a full-disk encryption , I want it to be compatible with existing LUKS, just add another key, and store it in the TPM.
4
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1answer
519 views

Can auditd track events that occured over NFS

I have multiple servers mounting a NFS shared called /opt/WHATEVER from Server X. Server X has auditd enables with rule: sudo /sbin/auditctl -w /opt/WHATEVER -p rwxa When events occur on Server X ...
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2answers
146 views

how to protect a personal computer? [closed]

I am Linux user with no knowledge on security , up to now i dont know that is my system was in attack or not . I havent felt anything wrong with my system . but every Computer user must have some ...
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1answer
5k views

How to use http-get-form in THC-Hydra?

I've been messing with Hydra (Brute Force) to solve the "Damn Vulnerable Web App" brute force section but the problem is when I use http-get-form it said: Warning: child 1 seems to have died, ...
5
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1answer
133 views

Testing a chroot environment for privilege escalation vulnerabilities

I'm looking for holes in my current implementation of a chroot jail that I have implemented for a group of users. Is there anything I can do better here? I utilized the following packages: RHEL6 ...
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2answers
232 views

How likely is an infection with an outdated skype on linux? [closed]

Today I found an article about a skype hotfix and noticed that the repo I use on my linux notebook: deb http://download.skype.com/linux/repos/debian/ stable non-free Doesn't have the new version, ...
4
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3answers
235 views

What would the cryptographic impact be of knowing the output of /dev/urandom?

Another noob question, I know, but something I'm unsure about. If I somehow magically knew the output of /dev/urandom at any given time, how much would that weaken a given encryption system? Or, ...
4
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1answer
242 views

Are we under hacker control?

We have a Web Server that mount Centos. Onto that WS there is an Apache (version 2.2.3) and some sites. You can log on only if you have a certificate (for root user) or via ftp (a restricted ...
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2answers
2k views

Security Concerns with X11 Forwarding

What are some of the security concerns and reasons either for or against allowing X11 Forwarding. I have generally taken an approach of not allowing it under the blanket guise of security. Recently, ...
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3answers
469 views

Danger of Path Traversal Attacks

I have setup a test application in Linux. I havent checked for paths in it, so if user enter /etc/passwd , then that file gets displayed to him. However, I want to understand what more can be done if ...
9
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4answers
534 views

What would happen if one of the popular Linux repositories is hacked?

Even though most people consider downloading your Linux software from you own distribution's repositories as safe, thinking about the scenario where a repository gets hacked sounds thrilling. What ...
4
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1answer
4k views

what does it mean to be setuid root?

I am reading Tanenbaum's Modern Operating Systems 3e. He says "Suppose that the program being attacked [with malicious code] is SETUID root in UNIX (or has Administrator power in Windows). The ...
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3answers
600 views

If I have two identical linux virtual machine images, will they generate identical random numbers?

A really noob question, I know, but something I was wondering about this morning. If this were the case, would they encrypt things identically? Or maybe someone could direct me to a helpful research ...
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4answers
4k views

What do I need to configure, to make sure my software uses /dev/urandom?

When setting up a server, what configuration changes do I need to make sure that all of the software uses /dev/urandom instead of /dev/random? Some servers don't have much entropy in the entropy pool ...
4
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3answers
818 views

Pseudo Random Generator is not initialized from the (entropy pool)?

The RHEL5 manuals state that /dev/urandom will use the entropy pool until it's exhausted, and then it will resort to a fall-back pseudo-random algorithm, so that it will never block. But when ...
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4answers
11k views

Netcat IP Spoofing

I am connecting to a server nc -v 192.168.0.1 1111 But I want to do IP spoofing because the server on 192.168.0.1 only accepting commands from 7.7.7.7. We are two friends, I am 192.168.1.1, and my ...
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1answer
410 views

Sending Commands using Hping3

I want to send my command to destination server. I am using hping3. And; hping3 -p 9999(running daemon and commands executing on this server) -S 127.0.0.1 I want to send my command. How to?
11
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4answers
2k views

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 ...
2
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3answers
958 views

discover virus or spyware under Linux

I suspect to be the target of very skilled hackers. 5 or 6 years ago I found spyware on my Linux webserver, it was lkm masked as ppp_deflate module with md5 hash hijacked. I mean with the same md5 ...
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2answers
1k views

NSA RHEL5 Checklist

The NSA has came up with the "Guide to the Secure Conguration of Red Hat Enterprise Linux 5" (http://www.nsa.gov/ia/_files/os/redhat/NSA_RHEL_5_GUIDE_v4.2.pdf) I have read through this guide and it is ...
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2answers
559 views

Allow apache to write to users' .ssh dir's

I know the title is just baiting the "your setup is insecure", but allow me to explain. I'm working on an application which aims to allow clients to rsync over SSH to our server. We need a web ...
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1answer
248 views

Looking for virus under Linux [closed]

if I am looking for a virus/spyware under linux, where should I have to look for to find it ? I suspect to be the target of very skilled hackers. 5 or 6 years ago I found a spyware on my linux box, ...
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1answer
119 views

Network abnormally slow during night hours

My network recently the last week as become abnormally slow around 11 pm. Very slow buffering youtube videos during all hours. Ive recently purchased the new router about two months ago but not ...
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3answers
3k views

Besides OpenVas and Nessus, what are my other options for vulnerability detection?

I know of Nessus (which is $1300 for a pro feed) and OpenVAS (which I don't like). I use Linux so do I have any other options for vulnerability detection?
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7answers
5k views

Physical computer security, how to disable USB ports when the computer is 'locked'?

Lets say my PC & server is in an environment where a theoretical attacker has physical access to the machine while I'm not there. Now the data is encrypted on the hard drive with TrueCrypt. ...
3
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2answers
1k views

What are the best IT auditing guidelines for Red Hat Linux 5.x+, including the critical data protection?

Currently, I am a junior application consultant and we are maintaining huge amounts of redhat machines as servers. I am given the chance and liberty by my boss (unbelieveable!) to go do my own ...
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0answers
261 views

Any suggestion for a good readerless smart card (security token) solution? [closed]

I'm developing a small CRM application that will have to store some sensitive data and I would like to (optionally) supply my users with the possibility to use a readerless smart card (aka "security ...
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3answers
4k views

Which tool (apart from nmap) can I use to scan a range of IPv6 addresses? [closed]

When I try to use nmap: # nmap -sP -6 FE80::1-234 [...] Failed to resolve given IPv6 hostname/IP: FE80::1-234. Note that you can't use '/mask' or '[1-4,7,100-]' style ranges for IPv6.[...] What ...
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2answers
308 views

vulnerable getlogin

I was reading "A taxonomy of Coding Errors" and I have a doubt regarding the point mentioned in C/C++ >> API Abuse >> Often Misused: Authentication(getlogin). I fail to understand the attack vector ...
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2answers
682 views

up2date tools for security audit linux / centos

I'm setting up a new CentOS 6 server and am looking into some security audit tools to validate my configuration and to point out weak spots in the server. There are a lot of non up2date tools out ...
12
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2answers
4k views

Available Resources for Securing RHEL 6

Some in our infrastructure group want to upgrade to start taking advantage of the new features in RHEL 6. In the past, I have relied on the NSA Guide to secure RHEL 5 and CentOS 5 installations. I ...
5
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2answers
272 views

Securing data on laptop's hdd

I was wondering which is the best way to secure/encrypt data in the hard disk on a laptop that runs Ubuntu Oneiric? Setting LVM encryption? I am mostly concerned about having my laptop lost or what ...
1
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0answers
254 views

Unauthorised Perl Scripts [closed]

One of my servers just had the memory exhausted by a load of Perl scripts, we use plesk and they seem to have appeared under the /var/www/vhosts/domainexample.com/cgi-bin/ directory, I managed to stop ...
7
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2answers
314 views

In Linux, when I consider trusting a new software source, what do I need to evaluate?

When I'm using the Linux software PackageKit, I get confused about what specific items of information I will need in order to decide whether to authorize software installation from a new software ...
7
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3answers
503 views

How to gain a shell?

I'm doing an exercise (exploit-exercises.com) that requires me to gain access to a shell running as another user. My question is this: I can create application that is guaranteed to be run by the ...
7
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6answers
8k views

Good file encryption tools

Could you please help me find a good file encryption tool? The target OS is Linux, but tools for Windows are welcome, too. FOSS tools are preferred. The tool must be reliable both for the recovery of ...
11
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3answers
3k views

Installing Development Tools on Production Server? Security Risk?

I am using an Amazon Linux EC2 instance as a web server. My web app uses ImageMagick. Because the Amazon Linux (CentOS) repository doesn't include an up-to-date version of ImageMagick, I am compiling ...
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5answers
2k views

How can I remotely wipe the contents of a Linux Laptop if its been stolen?

I am currently investigating using Linux Laptops for my development team. We currently run Windows. The one advantage that keeps coming up for Windows over Linux from a system administration / ...
3
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2answers
387 views

Security for home server, wiki

I recently set up my own home server, running Ubuntu linux. The intent I'm having for this is to have a private wiki for my family, so we can have a place to collect information like phone numbers, ...
2
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2answers
1k views

How do I figure out how malware infected my server, and the subsequent sites on the server?

I recently was in charge of fixing our server at work, and cleaning the sites on it. We were infected with some malware that injected some code into some of our clients websites. Apparently, there was ...
2
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3answers
2k views

Writing a sample virus (not harmful)

I don't know if such a question is allowed on this site, sorry if it's not For educational purposes I am asked to write a small virus running on Linux, which should just be able to inject itself into ...
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 ...
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3answers
3k views

How to scan USB drive with clamav on Linux

Is there a way to scan the entire drive including auto-run and all partitions, including the master boot record (MBR)?
3
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0answers
106 views

Apparmor policies w/ subprocess failing [closed]

Can anyone possibly explain why Apparmor is not picking up profiles for sub-processes of a process? Right now we use God to launch an unstoppable Ruby process (in this case it's /usr/local/bin/remote) ...
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5answers
831 views

What voip client support manual encryption?

In pidgin there is a plugin that we can use to encrypt our messages in chat windows .. Is there anything simular for voip (pc to pc) ? any client that support manual encryption for voice data?(linux)
4
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1answer
768 views

Why ESTABLISHED,RELATED for INPUT only?

In many places and tutorials I see people add this line to their iptables: -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT And they do it only and only for "INPUT". What about OUTPUT and ...
4
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1answer
2k views

Benefits to BlackArch over Kali

Besides BlackArch having a cooler name and the whole Ubuntu vs. Arch Linux thing, what are the relative benefits of BlackArch over Kali? Are the tools broadly the same, or does one have better ...