Securing Linux systems and applications; understanding Linux security features.

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Can I use Kali Linux when I learn Backtrack well?

I'm new to security issues and I am considering buying a course at ELearningSec (beginners course,of course). I am planning to work in a company and want to learn about offensive and defensive skills ...
3
votes
2answers
429 views

Does CVE-2015-5352 work if there is no active X-Server?

My security program shows that one of my servers is vulnerable to CVE-2015-5352. If X-Server is not running (not even installed) is the system really penetrable by that vulnerability?
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3answers
112 views

Reverse Engineer and Exploits researching [closed]

Can some one give me a start point for finding exploits in software and reverse engineering? I need some kind of a book or a site... I have background with programming with high and low level such ...
108
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8answers
16k views

Are there technical differences which make Linux less vulnerable to virus than Windows?

What makes Linux so different than Windows in terms of anti-virus needs? My question is not if I should get an anti-virus for my Linux. I perfectly understand why an AV is important. I would like ...
2
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2answers
699 views

Log information for SIEM auditing in Linux

How can I know what all types of events generated by Linux. I can get this from the logs, but reading logs and noting ID's is very time consuming. All events might not be triggered. I need this ...
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2answers
301 views

Use of Nmap ssl/http md5 and SHA1 hashes

I have below stated result on of the system by map: 443/tcp open ssl/http Apache httpd 2.0.52 ((CentOS)) | http-methods: GET HEAD POST OPTIONS TRACE | Potentially risky methods: TRACE |_See ...
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2answers
314 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 ...
4
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2answers
94 views

Is it a good practice to use certificates as a mean of client identification in a cloud environment

My software system is running a cloud infrastructure where having Linux machines VPN into OpenVPN gateway is a setup requirement. Also, there may be cases when software on the aforementioned Linux ...
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3answers
5k views

Is Linux spying on its users? [closed]

If you install some kind of Linux distributions on your computer, is their a possibility that their owners may spy on you? For example, can Ubuntu, Kali or Arch linux send data to its owners on what ...
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1answer
76 views

Gnome-keyring iteration count location

I know that Gnome-keyring hashes the master password between 1000 and 2000 times. It picks a random number. I would like to ask where it saves this number, what is the location of that file? As far as ...
16
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2answers
2k 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 ...
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1answer
96 views

Time-based password change [closed]

I have created this script and it runs great, but important questions remain. Is this script useful and secure? Does it have any possible problem or weakness? root@010010:/# ls -la /root/...
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4answers
2k views

Add a file as entropy source for /dev/random

What I have: A large file containing lots of secret, true-random bytes (yes, I'm sure they're not merely pseudo-random). I'll call it F. What I want to do: Tell Linux that it can use this file as an ...
11
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3answers
10k 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 ...
2
votes
1answer
252 views

Can BIOS firmware log keyboard input? If so, is there any way to detect and prevent it?

Recently I purchased a server board made by Lenovo with a "Intel Management Engine" inside BIOS. It is said that it is able to intercept and redirect keyboard input, even if an operating system is ...
3
votes
3answers
1k views

Storing SSH private keys on an Android device

(I'm not sure if this better belongs on unix.se or android.se, but since it's primarily security-related, I'm asking it here) I use my Android device to access servers for quick on-the-go ...
1
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1answer
1k views

ARP - forwarding or dropping with IPtables

I've been trying to ARP poison my home computer and router (intended to learn and discover the networks behavior). And with success. The whole time I've been using: with open('/proc/sys/net/ipv4/...
5
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1answer
436 views

What are the mitigating factors for CVE-2015-5364?

CVE-2015-5364 describes a UDP based DoS vulnerability in the Linux kernel that can be used to deny processing cycles to the host operating system and its applications. https://access.redhat.com/...
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2answers
199 views

Why does Android use SELinux?

To restrict/sandbox processes Android uses SELinux. Why was that chosen and not the linux capabilities or cgroups+namespaces solution? After all the cgroups+namespaces is kind of home grown for them ...
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1answer
414 views

If someone downloaded 600GB , can that be ddos attack [duplicate]

Last night some one exploit some vulnerability in my site and then upload php script in my images folder. I have the Amazon EC2 server with centos. Now the Hacker downloaded 600GB and increased my ...
2
votes
2answers
232 views

How secure is loging into internet banking via an https library?

My bank does not have an API so I want my server to log in and check incoming payments to notify me if a client has paid or not. I would like the server to log in and scrape using Beautifulsoup and ...
4
votes
9answers
1k 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
243 views

What is a Truecrypt alternative with deniable encryption for linux? [closed]

Preferably an alternative that is Free Liberating Open-Source Software/ FLOSS. I would have used Truecrypt, but it has been discontinued.
4
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1answer
504 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. ...
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2answers
943 views

UEFI secure boot and rootkits

I heard that with UEFI secure boot enabled a custom kernel module that is not signed will not run, hence a rootkit might be difficult to install. Can a secure boot really block rootkit modules from ...
3
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1answer
137 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 ...
2
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1answer
237 views

PPP over SSH - is this correct?

I see a lot of talk online about whipping up a VPN connection using PPP over SSH. This term confuses me, as SSH is an app tier protocol and PPP operates on the data-link layer. So, my question is: ...
3
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1answer
59 views

Unauthorized file writes on Linux

Suppose my web browser or any other web-connected app has a minor security hole that won't allow an attacker to run code but will allow them to write a piece of text into a text file I own. On a ...
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2answers
785 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 ...
11
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7answers
5k views

Secure memcpy for pure C

Buffer overflows are nothing new. And yet they still appear often, especially in native (i.e. not managed) code... Part of the root cause, is usage of "unsafe" functions, including C++ staples ...
5
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1answer
97 views

VirtualBox: Ubuntu With or Without Virtual Hard Drive

I've been working on a setup using VirtualBox that uses the Whonix Gateway as a Tor middlebox and I am planning on using Ubuntu for the workstation. I don't plan on storing any information on the ...
2
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0answers
410 views

Is XSP suitable for Internet facing, production hosts? (either self hosted, as an Apache plugin, or FastCGI)

XSP is portable version of ASP.NET that allows for operation on OSX, Linux, and Windows. It's an alternative to IIS, and hosts its own web server, or can plug into existing web servers such as Apache....
14
votes
1answer
8k views

Diffie Hellman parameters still calculating after 24 hours

I have a fresh install of Arch Linux on a RaspberryPi model B. I'm setting up OpenVPN and using easy-rsa with OpenSSL 1.0.2d to generate initial keys and certificates. All went fine until I ran ./...
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2answers
13k views

Test firewall rules (Linux)

I have a question about how to test the firewall rules. To be more specific, for academic purpose I have to set up a machine which will accept all kind of packets o a specific interface. I added an ...
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2answers
5k views

Do these regex show that I was hacked?

What do these regex commands mean? I found them when I ran the history command: grep --include=\*.php -rnw . -e "update.creditcard" grep --include=\*.php -rnw . -e "e41e" grep --include=\*.php -rnw . ...
38
votes
9answers
7k 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. ...
2
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0answers
59 views

Can high network usage be detected and prevented in Tor? [closed]

I've already asked this question here but as of yet it has no views/answers. I was wondering if there is any way for Tor to detect high network usage in the context of transferring large files using ...
5
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1answer
701 views

Does Linux kernel use DEP for kernel memory?

Does the Linux kernel use DEP internally for its kernel memory? In other words, does the Linux kernel take care to ensure that, when the kernel is executing (in kernel mode), every executable ...
3
votes
2answers
278 views

What are the security risks in leaving 'sudo' inside my production code?

I have a script that can only run successfully with root permissions But in development it's really hard to run with root permissions (in my development environment) so I add 'sudo' when ever it's ...
3
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2answers
212 views

Questions regarding Bad USB exploit

I own a Netbook and my external DVD Drive is possibly infected with Bad USB. If I install Ubuntu using this infected DVD drive, could my system be taken over during installation process or later when ...
4
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1answer
317 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 ...
15
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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 ...
17
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3answers
1k 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 ...
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3answers
107 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 ...
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2answers
77 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 ...
1
vote
1answer
125 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 ...
6
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2answers
4k views

Security of LXC compared to OpenVZ

For years, I'm now using OpenVZ on my server, but support discontinued for Debian and Ubuntu, current releases seem to focus on LXC now, which is not a bad idea from the point of comfort. But what ...
2
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1answer
57 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 ...
2
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1answer
1k views

How configure tomcat 7 SSL to use AES-NI?

My server has AES-NI and I would like tomcat 7 to make use of this but I am not really sure how to make that happen or where to even start looking. I am quite familiar with tomcat administration, and ...
9
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2answers
352 views

Bootstrapping an EC2 Spot Instance

I'm considering using EC2 Spot Instances in an automated fashion (ie create a script that will request EC2 Spot Instances that will run unattended). For this specific use case, I'm happy to lock down ...