Securing Linux systems and applications; understanding Linux security features.

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Encrypt-function inside PHP code that you have to publish

If you write a PHP application, where you have to deliver the compiled code to the customer, how could you include a functionality to send encrypted data from that application to others, and include ...
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3answers
573 views

What is the most secure way to set up web server user permissions? [closed]

The default Debian way of setting up a common web server (Nginx) is to run the main process as root and unprivileged workers as www-data. In order to allow for the worker processes to read/execute web ...
1
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0answers
422 views

GnuTLS ServerHello exploit (CVE-2014-3466) - how to verify?

So pretty much all of the GNUTLS world is worrying about CVE-2014-3466. I checked my Kali and it responds with this - # apt-cache rdepends libgnutls26 | grep -v lib Reverse Depends: ...
3
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4answers
181 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 ...
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3answers
9k views

Is a rand from /dev/urandom secure for a login key?

Lets say I want to create a cookie for a user. Would simply generating a 1024 bit string by using /dev/urandom, and checking if it already exists (looping until I get a unique one) suffice? Or should ...
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2answers
79 views

Encryption in Linux: covenience and security [closed]

I was using TrueCrypt until recently, until one of two options has happened: either it was discontinued or its web-site truecrypt.org was hacked. Any option implies that I don't trust it anymore. So ...
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1answer
119 views

Using a TPM with Linux

I have the need for a company laptop (Dell e6540) that contains our java application on it to go out for evaluation purposes. For this reason I would like to make sure that the HDD is protected from ...
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0answers
54 views

My server has been brute forced what now? [duplicate]

I have installed a raspberry pi for fun at home. I opened the port 22 and this morning I was concerned about someone brute forcing my server. I ran this query : cd /var/log;zgrep ssh auth*|grep ...
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1answer
52 views

How to secure an embedded linux image

I'm building an image with openwrt sdk and i want to secure my image (by encrypting filesystem for example).. How can i do that to prevent anyone from seeing my sscripts or programs running ?
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5answers
1k views

Hackable linux distributions

A few years ago we had that awesome Linux distribution called Damn Vulnerable Linux. But unfortunately it looks like the project is dead. So my question is are there other Linux distributions which ...
6
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2answers
139 views

How often is ASLR randomness refreshed, in Linux?

Most Linux distributions now use ASLR for many programs, to randomize the layout of memory. How often is the randomness used for this changed? If I re-run the same program multiple times, will it ...
0
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1answer
84 views

VPN tunnel in VPN tunnel

I'm wondering if there is an easy way to establish VPN tunnels through other VPN tunnels to get onion routing like properties (sender anonymity). Since VPN builds a tunnel, it should be easy to set up ...
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4answers
161 views

How to detect credit cards harvested from memory?

Had a chat recently with PCI compliance specialist and got to realize there is a way to steal raw data from Apache / Nginx memory e.g. credit cards. It's called "harvesting" and becomes pretty common. ...
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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. ...
6
votes
4answers
947 views

Security of the KWallet password encrypting application?

According to http://gaganpreet.in/blog/2013/07/24/kwallet-security-analysis/ , the KWallet password management system is quite weak, it uses key splitting, Blowfish 56, and no salt. The key ...
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3answers
143 views

How to secure ubuntu desktop after a hack? [closed]

I have two ubuntu laptops that were recently compromised. I understand that it's probably a fruitless endeavor to try to find the hacker. I want to know how to secure my ubuntu desktop so that the ...
3
votes
2answers
287 views

How to pass PCI DSS 2.0 anti-virus requirement (5.1) on Linux?

PCI DSS 2.0 Requirement 5.1 states: 5.1 Deploy anti-virus software on all systems commonly affected by malicious software (particularly personal computers and servers). This requirement ...
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3answers
100 views

How to set iptables to drop packets that I'm not listening on?

I've got a Kali Linux box I use for pen testing. I would like to configure my machine to DROP incoming packets, but only when I'm not listening on them. e.g. if I run a netcat listener on port 80, I ...
2
votes
2answers
108 views

security via chsh

I am developing a program that I want people to be able to connect to and use via ssh. I've decided a simple way of doing this would be to create an account for them on my linux server, and change ...
3
votes
1answer
443 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
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3answers
111 views

Securing data on a server

I have a server which has 'loose' physical security (somewhat easy for the entire server to get stolen). For the sake of the question, let's assume that anyone can access the server physically, what ...
2
votes
3answers
314 views

Encrypting Backups on Linux

I'm working on an automated backup solution to protect my files on my Linux servers. However, I'm not sure about how to securely encrypt the resulting archives. I am using 64bit linux, and I am ...
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0answers
53 views

How should I configure my Tor-dedicated firewall for optimum security?

I'm setting up a Tor-based isolating proxy using the 'Anonymizing Middlebox' iptables rules specified here: https://trac.torproject.org/projects/tor/wiki/doc/TransparentProxy i.e. iptables -t nat ...
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7answers
4k views

Any comprehensive solutions for binary code protection and anti-reverse-engineering? [closed]

Does anyone know of good products with comprehensive binary hardening and anti-reverse-engineering features? Or better, has anyone seen an independent review comparing products that perform these ...
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3answers
333 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 co-location place. The servers and firewall all have a remote management port (KVM, ...
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1answer
38 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 ...
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3answers
103 views

How bad is it to *not* reboot a server after kernel updates?

I’m administrating a few Debian Linux server, and install package updates when apticron notifies me of them. Occasionally I see updates to linux-image-[something] packages, but don’t bother to reboot ...
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1answer
89 views

Analyzing a suspicious email

Today I received a very suspicious email on my gmail account. When I analyzed the content of the message, this is what essentially made up the message. <center> <a alt="" ...
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2answers
76 views

Ubuntu LVM LUKS Encryption

I've been reading about Ubuntu LVM Encryption, and I understand that it supports the use of Linux Unified Key Setup (LUKS) during installation, which is a block level encryption that encrypts the ...
4
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1answer
114 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 ...
1
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1answer
46 views

How to validate the confirmation link received when publishing a new PGP key?

I find PGP to be quite a complex subject. I have gotten to a point where I need to give a client a public key for encryption. I have successfully done my homework, generating a public key from my ...
2
votes
1answer
94 views

Security Features enabled in Linux Debian and Ubuntu

i am actually doing some tutorials about ROP on Linux. So i tried to follow the tutorial and compiled some of the example codes to try ROP in a small scope. But actually when i am trying to exploit ...
4
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2answers
530 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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3answers
93 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 ...
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1answer
158 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 ...
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2answers
433 views

Running proprietary software on Linux safely

As a summer project, I'm looking to prevent any piece of proprietary software like many games I run from have access to my personal files. After looking a lot at sandboxing, I've decided that anything ...
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2answers
145 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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1answer
90 views

Most secure SSH server [closed]

Which SSH server (compatible with Debian Wheezy) has the fewest (if any) exploitable security bugs?
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4answers
179 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 ...
1
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1answer
110 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 ...
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1answer
669 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 ...
1
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1answer
140 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 ...
1
vote
1answer
315 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 ...
13
votes
2answers
548 views

Getting exploit reliability when using the off by one framepointer overwrite on linux

We have a program that is vulnerable to a one byte frame pointer overwrite. The stack is marked executable, the Linux machine has aslr disabled, stack cookies are disabled, and it's a little endian ...
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vote
4answers
264 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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5answers
177 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?
0
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1answer
33 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, ...
6
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2answers
387 views

What features do you look for in an Enterprise Log Management solution?

This question is for IT Pros, and people who manage a company's infrastructure. Developers should see this related answer for tools geared for them. What are your requirements for such a Event Log ...
3
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1answer
69 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.
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votes
1answer
2k 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 ...