Securing Linux systems and applications; understanding Linux security features.

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2
votes
1answer
18 views

How do I customize /proc permissions?

So that: Only process owners, and root, can access information about their processes, Or, at the very least, cmdline permissions are only readable by root, and My system (CentOS 6.x) still runs ...
-1
votes
0answers
61 views

credit card number search software for Linux and Windows [on hold]

Can anyone recommend free software that will search all the systems files for credit card numbers? The software should produce a log output of the result. I need one to work on Linux and ideally also ...
0
votes
2answers
93 views

Store a file on a harddisk without root having access to it

Is there a way to store a file on a disk as a user so that even the root user has no access to it? I tried EncFS but that is no solution because the root user can switch to every user, so he/she can ...
-1
votes
1answer
43 views

How should privileged accounts be secured in both Linux and Windows?

I have recently started work in application security at a mid-sized firm, having transitioned away from 5+ years in security consulting (pentesting, etc). One of the biggest challenges I see here from ...
0
votes
1answer
28 views

Samba Exploits and Fixes [on hold]

What are the common ways I can exploit Samba and what are the solutions to protect myself from them? I am trying to find exploits to see where I can then fix them on Debian.
0
votes
2answers
55 views

Clarifying MITM attacks and Digital Certificate requirement

We are running a Portal application for our client with Payment Gateway integrated. Payment gateway uses SSL as it is suppose to be . The concern for me is that our Portal application does not use ...
0
votes
1answer
25 views

benefits of xinetd for a web server

What are the pros and cons of using xinetd for a web server running on a VPS. Assume the following measures have already been taken to secure the system: system hardening, latest updates, minimal ...
0
votes
0answers
5 views

How to use OpenVPN on Whonix Workstation? [migrated]

I've checked the documentation and googled it like a mad man. It's supposedly straight-forward as it should just go through the gateway with no problems. But I am getting one error after another with ...
4
votes
2answers
132 views

You've just acquired a newly created CentOS server, what should you do to secure it?

I've just acquired a new CentOS server, which will be hosting a Ruby on rails application, it is public facing. What should I do to secure this server?
6
votes
3answers
104 views

How to sandbox Iceweasel (Firefox) on Debian? [closed]

Are there any tools for sandboxing Iceweasel (Firefox) on Debian systems? I'm mostly interested in tools distributed by Debian. (An equally trustworthy source would be second best.) (I suppose that ...
1
vote
2answers
57 views

What's there to harden for a home Unix-box behind Comcast cable modem?

I'm learning that much of the security advice I come across under the "hardening" heading simply does not apply to a single-user home desktop box sitting in a private wireless IPv4 LAN behind a ...
-1
votes
0answers
41 views

questions about data/encryption of a linux directory [migrated]

i have a directory full of sensitive data and want to encrypt this directory to protect against outside attackers. i still want to be able to read from the directory and display this data onto a ...
2
votes
2answers
29 views

Is there a website or other resource that lists operating systems/platforms and the included root certificates?

I need to choose a certification authority (CA), to get a certificate, but I noticed that there are several of these only present in some operating systems/platforms like windows. I need to choose one ...
3
votes
3answers
100 views

Protect partition from formatting

How can i protect my Linux and Windows partitions from being wiped,from a windows installation CD,with password?
-2
votes
1answer
50 views

Proccess to exploit an OS vulnerability [closed]

What are the steps to use an exploit on an OS vulnerability? I tried the popular ms08-067 on an XP machine, following a guide found on the internet, discovering Metasploit etc., but I can't figure ...
0
votes
1answer
30 views

Wireshark: could “Follow TCP Stream” yield an empty window? or is it a bug?

I am capturing a pop3 netcat connection (port 110) using Wireshark, on Debian linux (Kali). After filtering packets with (tcp.port eq 110) I get few packets but once I R.Click on any and click "Follow ...
2
votes
3answers
74 views

How to setup a dedicated home machine (Linux) for secure transactions?

I would like to set up a computer at home (preferably running Debian, or some other flavor of Linux) to be used only for secure financial transactions. The idea is that, by strictly limiting what is ...
0
votes
0answers
13 views

How to get system-wide use of Intel's AES-NI acceleration with OpenSSL 0.9.8? [migrated]

I found the following instructions to get Intel's contrib OpenSSL 0.9.8 engine code on some Westmere-based systems that we have: $ wget https://www.openssl.org/contrib/intel-accel-1.5.tar.gz $ tar ...
0
votes
2answers
58 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 ...
0
votes
0answers
8 views

Can I specify PBKDF2 rounds to use with LUKS/dm-crypt? [migrated]

I have encrypted my root partition with dm-crypt/LUKS/cryptsetup on Ubuntu 12.04. Since it uses PBKDF2: Is it possible, during creation of the encrypted disk, to specify a custom amount of PBKDF2 ...
1
vote
0answers
387 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: ...
0
votes
2answers
78 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 ...
0
votes
0answers
53 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 ...
0
votes
1answer
44 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 ?
6
votes
2answers
122 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
votes
1answer
80 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 ...
1
vote
4answers
157 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. ...
2
votes
1answer
113 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 ...
3
votes
2answers
203 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 ...
0
votes
3answers
90 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 ...
0
votes
3answers
130 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 ...
2
votes
3answers
110 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 ...
0
votes
0answers
45 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 ...
12
votes
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 ...
2
votes
1answer
83 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="" ...
1
vote
3answers
98 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 ...
0
votes
1answer
60 views

In return to libc how do you know the address of system() in a remote machine?

I have the following scienarion: a vulnerable program running in a server and can be accessed using netcat I have a copy of that program locally and I can exploit it locally using ROP: ./vuln ...
0
votes
2answers
70 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 ...
1
vote
1answer
44 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
80 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
votes
1answer
113 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
vote
2answers
94 views

Open Source OS - code you see vs code you get

In this question I will use the example of Linux OS, but I am also interested in general situation. Linux OS distributions are famous for being open source and thus rather secure. But how can you be ...
2
votes
2answers
200 views

I've found security vulnerability in current linux distribution. What next?

I've installed ubuntu server 12.04 on VM two weeks ago. I've created regular snapshots. XXX time ago I've noticed unusual activity and I've found that a backdoor was installed into my server. One of ...
1
vote
3answers
92 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
vote
1answer
36 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
votes
1answer
143 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
votes
1answer
326 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 ...
-4
votes
1answer
81 views

Most secure SSH server [closed]

Which SSH server (compatible with Debian Wheezy) has the fewest (if any) exploitable security bugs?
46
votes
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 ...