Securing Linux systems and applications; understanding Linux security features.

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2
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2answers
908 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 ...
1
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1answer
50 views

updatedb and encrypted home folders: Does it store unencrypted file and folder names somewhere?

When you encrypt your home folder in Ubuntu and Debian, it protects not only the file contents but also the file and folder names. Yet I see that updatedb and locate works in Debian. When I run ...
0
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1answer
63 views

How do I secure X server against spyware in a GUI application?

Suppose you have a GUI application, that potentionally may be too curious about your environment, such as the list of window titles. How do I limit application's ability to enumerate windows, capture ...
25
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3answers
23k 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
370 views

RHEL 6: PHP 5.3.3 - Is it inherently insecure?

I am talking about the PHP 5.3.3 package that is available in the Red Hat Enterprise Linux repository, running on Apache. From what I can see, as of RHEL 6, it is the latest version (no updates ...
-1
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1answer
132 views

Which hardening methods are used in large linux desktops environments (i.e. Goobuntu)? [closed]

Im courious to know about how these large enterprises secure their linux desktop as Google does with ubuntu LTS. I am the only user at home with linux on the desktop and had already created some ...
0
votes
1answer
79 views

Limiting account access based upon NIC used to connect on Linux

I have a server which has multiple NICs (ignoring redundant pairs): 'inward' facing production (connects to other servers); 'outward' external facing production (connects out to the internet via a ...
1
vote
1answer
75 views

Linux file information leakage

What information is kept in a linux file about the user and/or system that created it? I want to make some files publicly available, posted on another server such as GitHub or FTP, but I'd rather the ...
4
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2answers
193 views

Why was LibreSSL PRNG unsafe on Linux?

From the source: https://www.agwa.name/blog/post/libressls_prng_is_unsafe_on_linux The first version of LibreSSL portable, 2.0.0, was released a few days ago (followed soon after by 2.0.1). Despite ...
3
votes
2answers
977 views

Possible implementations of networked+encrypted filesystem

Is it possible to implement scheme where remote server just share its filesystem (or resizable container file in it) and it's locally encrypted and mounted? And what is best practical method? (On ...
4
votes
2answers
704 views

What Ubuntu packages are still affected by gnutls bug CVE-2014-0092?

Right now the internet is abuzz with news about a severe breach in GnuTLS. An update to the relevant GnuTLS packages has already been released. But I am worried whether some packages might have had ...
3
votes
1answer
845 views

Enterprise Anti-virus for Linux?

I know this question is probably at risk of offending the guidelines but our IaaS provider was unable to offer us an anti-virus solution for our Linux servers. We are deployed in an enterprise cloud ...
4
votes
3answers
359 views

Is it possible to USB whitelist in Linux?

After watching Black Hat's presentation on the fundamental problems with USB "security", I'm wondering if there's a way to do USB whitelisting in Linux. Is there currently a mechanism that will allow ...
0
votes
3answers
95 views

Permissions security scenarios for a web server

Having /var/www/site.com owned by www-data:www-data with a 750 permission for directories and 640 for files, and having my user alexb added to www-data group, I found my self with permission issues ...
1
vote
1answer
245 views

how to protect my linux pc from wifi sniffing

I have a wifi shared connection with other flatmates and I'd like to know how can I protect my Debian pc from being sniffed. Should I use a wifi anti sniffer to detect if any wifi card is in ...
-4
votes
3answers
146 views

Is MS Windows more secure than Linux on this aspect?

The administrator account can be renamed which means the hacker needs to figure out two pieces of information : the user name and the password while there is always one root account in Linux named ...
0
votes
1answer
50 views

Throttle network based on OS [closed]

What do I need to learn/know to throttle a clients network based on his/her operating system. For example: Someone in my network using Kali Linux... I would like to throttle their traffic to ...
1
vote
2answers
91 views

Is it safe to create live usb on an infected system?

I am using Ubuntu 13.10. If my laptop is infected with malware, can I get rid of it by creating a live usb on it and using that live usb format and re-install the ubuntu ? I mean is it possible that ...
1
vote
2answers
338 views

Does the EICAR test work on Linux based antivirus scanners?

Does the EICAR antivirus test work on antivirus scanners for Linux? The EICAR test is described in more detail here: http://en.wikipedia.org/wiki/EICAR_test_file The reason I ask is that it requests ...
27
votes
5answers
5k views

Is Linux really that secure, with only root password denying external access?

While I was searching online for information about Linux security, the most typical explanation was: Linux is secure, because the root password is required to access the kernel and install new ...
1
vote
1answer
63 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
3answers
2k views

Is it better to use a root password, or use 'sudo bash'?

When I am doing a lot of sudo operations, I like to spawn a bash shell from sudo to make the operations go quicker. I am against assigning a root password because I do not like the root account ...
7
votes
4answers
269 views

DNS spoofing of linux distribution repositories

Question(s) Is it possible to "redirect" linux-update-repos via DNS spoofing (e.g. DNS cache poisoning) to a malicious website, so that harmful software (updates) will be installed, when running the ...
1
vote
1answer
382 views

Installing Joomla with nobody:nobody user/group (CentOS/cPanel)

If you are installing Joomla via cPanel's File Manager to your mywebsite.com (user mywebsite) account, you will upload the package to your server and extract the archive. All files will have the user ...
0
votes
1answer
83 views

How secure is user-mode Linux, in terms of protecting the host system?

Two questions about User-Mode Linux: Suppose that a privilege escalation attack is used to gain root in a UML guest. Assuming modern (3.0 or later) host and guest kernels, is it trivial to escape ...
5
votes
1answer
139 views

Is a Linux environment PCI compliant if the swap file is not encrypted and PANs are loaded into RAM?

Is a Linux environment PCI compliant if the swap partition/file is not encrypted and PANs are loaded into RAM by an application?
2
votes
1answer
68 views

Can a malicious user do any harm using /dev/kvm?

I'd like to know if giving access to Intel version of /dev/kvm on Linux to a user that just wants to spawn VMs gives him any extra privileges. That is, are her VMs subject to process scheduling just ...
3
votes
4answers
789 views

does switching to linux remove existing computer virus

if you change from a malware/spyware infected windows setup to a linux setup will infections migrate to linux if they were on the computer? (when you are hacked/infected is it the op system that is ...
0
votes
3answers
2k views

VPS Privacy: OpenVZ vs KVM vs Xen

Considering OpenVZ, KVM and Xen: Which VM technology is the most difficult for the host's administrators to access given an encrypted root partition? Can I have a reasonable expectation that rogue ...
0
votes
2answers
185 views

How exactly does this Flash malware function on Ubuntu?

In this video, an experienced Ubuntu user manages to infect his system with some sort of malware. This is the first example I've ever seen of truly successful malware in the wild aside from privilege ...
0
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1answer
289 views

Ubuntu 12.04 server attacked using Wordpress vulnerability (plugin?) [duplicate]

Env Rackspace cloud server Wordpress 3.9.1 Ubuntu 12.04 Linux web.mydomain.com 3.2.0-67-virtual #101-Ubuntu SMP Tue Jul 15 17:58:37 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux History These may ...
19
votes
3answers
2k views

Can Windows malware harm a Linux computer when it's executed with Wine?

I am an (Ubuntu) Linux user. Sometimes, I have to use Wine for running Windows executables. I would like to know if Windows malware (virus, trojan, worm,...), i.e. malware that was not intended to ...
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3answers
139 views

Help me catch someone red handed on our server.

I first tried to log in this morning and our password was changed on our ubuntu server. I contacted our server support and they told me that I had just been fat fingering the password. I thought it ...
1
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1answer
66 views

Running an Open Server (contents are visible)

I'm considering the possibility of running an Open Server, as I would call it, that is, a server where as much of its contents are publicly visible as possible. I would like to give read access to ...
0
votes
1answer
88 views

What Linux software can I use to explore entropy of a file?

I've heard of tools that could be used to graph entropy of a file. Is there a graphical Linux program that I could use for this job that would let me conveniently explore which blocks of a file have ...
2
votes
1answer
3k views

Is it safe to disable connection tracking in iptables?

While reading about NOTRACK target of raw table in iptables, I encountered an article suggesting that for certain traffic you could (or even should) disable connection tracking. The two examples were: ...
1
vote
2answers
137 views

the dangers of internet forums - what is FUD, what is not

I just visited a forum and a member knew what OS I was running without me saying anything (a not TOO common distro of linux). Now I'm not sure how he exactly he might have done it, or what information ...
35
votes
4answers
15k views

Should I get an antivirus for Ubuntu?

Considering the recent thread regarding anti-virus for the Mac I wonder how many of the arguments put forth are relevant today to Linux systems, specifically Ubuntu. There are no known Ubuntu ...
1
vote
2answers
171 views

How to hide or obfuscate the type of OS?

I get the OS type of a remote host by: connecting to an open port (telnet <host> 22); using Nmap (nmap -A <host>). What are techniques and how to hide or change the information about ...
0
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1answer
318 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 ...
2
votes
2answers
286 views

PHP shellcode inside /tmp. Is the server compromised?

I have a Debian 7 VPS that runs Nginx, PHP5-FPM and MariaDB. This server runs a couple of WordPress installations, phpMyAdmin and Roundcube Webmail. One is my personal blog running WP 3.9.1 and ...
0
votes
4answers
155 views

Can a virus on the host affect the VM guest [duplicate]

let me explain my problem. The wifi on my macbook suddenly stopped working so tried to use my usb wifi adapter on a linux VM. But the funny thing is that nothing works on the guest vm either... Well ...
1
vote
2answers
479 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 ...
2
votes
1answer
39 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 ...
5
votes
4answers
2k views

What are the most common files to check with File integrity monitoring software?

I have a file integrity monitoring suite and in it I have to select specific files and folders for it to monitor. There are some obvious services that I want monitored like our web-server. Is there a ...
0
votes
2answers
129 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
97 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 ...
13
votes
4answers
2k views

environment variable accessibility in Linux

Perhaps this is a trivial question, but how accessible are environment variables in Linux between different users? e.g. if Alice executes export FAVORITE_FOOD=`cat /home/alice/fav_food.txt` Can ...
0
votes
2answers
202 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
106 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 ...