Content related to computer security., i.e. content about policies, mechanisms, etc. needed make sure data is not leaked or corrupted and services available in all circumstances.

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1answer
57 views

How to securely download rpmfusion keys

The Actual Problem I am trying to solve I am trying to automatically configure my fedora installations via salt to automatically have the rpmfusion repositories installed. In order to do this ...
3
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2answers
121 views

How to implement logwatch functionality on top of systemd journal?

Logwatch scans logfiles with regular intervals, collects errors and stuff, then mails it to the admin. This was back in syslog and logfiles days. What's the corresponding solution for systemd's ...
0
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2answers
87 views

Which runlevel is best for a Linux (Debian) server (DBMS/SCM)?

I currently try to harden the system and the security of a Debian server running a database and a source code management. I just want networking and me (one user) to be able to login. Which runlevel ...
2
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2answers
53 views

Securely viewing an encrypted file

I have a file that is gpg encrypted. I would like to view the content of the file, but leave no trace of the output. Lets say for example that the encrypted file has some passwords, and I don't want ...
2
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2answers
304 views

Is a -rw-rw-rw- file really inaccessible inside a drwxrwx— directory?

Say I have a directory with these permissions: drwxrwx--- Inside this directory, a file with these permissions: -rw-rw-rw- Is the file readable/writable by everyone or not ? If not, how secure ...
4
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1answer
176 views

Myth or reality: SELinux can confine the root user?

I read or heard somewhere (maybe in LinuxCBT's SELinux course; but I'm not sure) that there are online Linux servers, for which the password of the root user is also given. The Linux server is ...
4
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1answer
131 views

Is there any point in using `sudo` when you are the sole user of your machine?

I'd like to know if there is any reason why I should use sudo instead of su, taking into account that I am the owner and sole user of my machine (and hence have root access whenever I want). Also, in ...
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0answers
132 views

Unable to set capability CAP_SETFCAP by user

The question is about capabilities. I need to allow user to set capabilities using setcap. When I call it by root all goes fine, eg $ sudo setcap cap_dac_override,cap_dac_read_search+ep ./bin_file $ ...
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1answer
52 views

securely automating a script which requires a key to do its task

I have a script that downloads bank transactions to store in a database. To get these transactions requires a password for each account. The database is encrypted and requires a key to access it. All ...
2
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1answer
182 views

I need find 1 simple rootkit to test chkrootkit in centos?

I want to find 1 simple rootkit to test chkrootkit (a tool used to detect rootkit). Please recommend to me 1 rootkit and show me how to set it up or install it.
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1answer
86 views

Which software supports DoD 5220-22-M 7 pass standard for SLES 10.4?

"DoD 5220-22-M 7 pass standard" is a secure deletion method. But what software supports it for a SLES 10.4 64bit?
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3answers
245 views

noexec on /tmp and /var/tmp directory

Our client servers are running old version of jboss (Jboss 4.0) which has lots of known vulnerabilities. Result is that the server is hacked and we are seeing some unknown executables running from ...
5
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2answers
636 views

Setting ulimit correctly for PHP on Linux

I have /etc/security/limits.conf set to the following: nobody soft nofile 409600 nobody hard nofile 1024000 phpuser soft nofile 409600 phpuser hard nofile 1024000 httpd soft nofile 409600 httpd hard ...
6
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6answers
179 views

File protection in Unix

Is there a way to protect a file in such a way that even root cannot delete it or rewrite it after creating it? I have a file which is created by root under /var/log/ and I want to restrict all users ...
1
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1answer
129 views

Hidding an encrypted folder in a shared system without root access (unshare -m)

I'm a graduate student trying to use a cluster at my university. These machines are shared, so I want to protect the source code I use (I signed a NDA, so I'm scared about publishing the code by ...
60
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19answers
8k views

Root access that can't change root password?

We are having a little problem on a server. We want that some users should be able to do e.g. sudo and become root, but with the restriction that the user can't change root password. That is, a ...
2
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1answer
522 views

Securest way to authenticate users against /etc/shadow using PHP?

This question became important to me, since I'm setting up a Horde environment and want to use the system accounts. Doing some search I found mainly 4 ways of doing that, which all seem to have some ...
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4answers
200 views

How do I search for all the folders that begin with a dot ( . )?

My server had been infected and the attacker spread a bunch of .5randomletters folders around my file system, with malicious code inside of them. I want to search for all the folders that begin with a ...
8
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2answers
274 views

How can I create a hard to kill process

I want to create a program that will be difficult to stop (even for the administrator) once it is started (with root privileges). Once started the process should continue to start itself at startup ...
4
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2answers
147 views

Finding the logs in a hacked server. [closed]

My server has been hacked and the hacker managed to ssh as root (I know, horrible mistake on my part). What files should I be looking for to discover the origin of the attack? (At least their IP). ...
2
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3answers
90 views

How do I disable and re-enable Java whenever I want?

For me Java is just a security threat. Not many legitimate Linux apps use Java. However there is an abundance in Java malware and malicious remote administration tools like Jrat among others. But one ...
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2answers
142 views

How is the loopback device traffic allowed?

How can I allow the traffic to be sent on the loopback device (lo)? What is the iptables command for it?
0
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1answer
265 views

iptables couldn't load target allow

I am using the command below to allow all traffic from hosts on my internal network but it says "iptables v1.4.18: Couldn't load target `ALLOW':No such file or directory". What is the problem here? ...
5
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1answer
33 views

Need More Information About KDE Job Notification

I installed Debian 7.2 on a new laptop a couple of days ago, and now I'm getting a strange job notification every once in a while. It just says the following: Source: ...
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2answers
325 views

Is NFS very secure? Secure alternatives [closed]

I know that there is a very similar question to that Is NFS Secure Over Internet, but I am asking a little bit different. I guess that NFS is not so secure, as I can learn from the internet and from ...
4
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3answers
663 views

Running Viber as another user while using “mine” X Server's microphine and speakers

I run Fedora with GNOME and recently installed Viber for linux. It's very good and all is working just fine. As Viber is not open-source software, I decided to run it as another user to make sure ...
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0answers
184 views

How to secure Apache/MySql/PHPMyAdmin against brute force/dictionary attacks? (Fail2ban?)

I'm wanting to run a publicly accessible server for web hosting. I'm interested in preventing brute force attacks made against PHPMyAdmin or any other form of authentication process I may include in ...
3
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2answers
82 views

Is there any mitigation against touch date/time forgery?

I have been using touch -t to change time of a file when I started using Linux, is there any mitigation against touch date/time forgery? Like, echoing original created date and time, even after using ...
31
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4answers
1k views

Why can't I execute shutdown when the permission is rwxr-xr-x?

I'm in /sbin and I see that shutdown has permissions rwxr-xr-x. Doesn't this mean that anyone can execute it?
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5answers
162 views

Can I stop SElinux from working?

I suspect that SElinux is backdoor and I want to stop it from working on my system. I want to stop it and delete it from the system also if that is possible. Questions How can I delete it without ...
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2answers
90 views

Is there any other way to restrict USB storage?

I have been using /etc/modprobe.d/blacklist.conf to restrict USB storage but all employees are given root permissions, so they are removing restriction very easily. What I'm looking for is is there ...
3
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2answers
119 views

SSH when to use public key and password?

I think I understand the difference between Public Key authentication and Password. But how do I decide which one to use and which one is most secure in what situation? Can anybody give me some real ...
2
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0answers
278 views

Intel Advanced-N 6235 wireless monitor mode problem

As far as I know, iwlwifi drivers (and this particular wireless card) support monitor mode. The only requirement is to install the latest driver from ...
2
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1answer
95 views

Could a hacker replace a Bitcoin wallet application with a malicious one in some Linux repository? [closed]

Bitcoin QT is arguably the most popular Bitcoin wallet application. If a hacker gets access to the data and the private key on some machine, he can steal all the Bitcoins from that wallet. Being a ...
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1answer
54 views

when update kernels do they close bugs?

I'm not an expert in linux but when I upgrade my kernel to latest stable one which is 3.12.2, does it close all security bugs? How linux security bugs be closed? by installing newer kernel or how ...
1
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1answer
600 views

AES-GCM 256bit for SSL on nginx

Does an option exist for AES-GCM 256bit encryption for SSL connections with nginx? If so, how can I configure this as the only cipher used with my server? (I'm hardening my router, so requiring the ...
4
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3answers
174 views

restrict student account permissions, give faculty access

I have set up two user groups, students and faculty on Ubuntu 12.04 and created a number of students and faculty accounts. The problem is a student can currently see & read all of the files of a ...
0
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1answer
154 views

iptables - why the stun, turn ports are not working to allow end points to access the server?

I have this iptables where all working except tcp/udp port 3478 and 5349. $ cat /etc/sysconfig/iptables # Generated by iptables-save v1.4.7 on Thu Nov 21 10:21:41 2013 *filter :FORWARD ACCEPT [0:0] ...
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1answer
79 views

Do I need to wipe and reinstall after possible hacker attack [duplicate]

Yesterday I noticed that the xterm title I use changed suddenly to something strange. So I suspect that someone hacked my Linux laptop (I'm using Arch). I changed the WiFi parameters (pass, essid) and ...
0
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0answers
42 views

Prevent scp from asking passphrase [duplicate]

I have enabled private key based access to my server. I have generated the certificates with a passphrase. So to ssh to that machine I have to do - $ ssh -i .ssh/id_rsa_server foo@example.com and ...
2
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1answer
364 views

Does this threat still exist: Linux keylogger without root privileges

http://superuser.com/questions/301646/linux-keylogger-without-root-or-sudo-is-it-real Or it's long gone as most of the new distros implement SELinux by default
0
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0answers
509 views

Fail2ban - alternative robust for enterprise protection against DoS attack in SIP and similar to fail2ban features

Is there any fail2ban like software for CentOS 2.6.32-358.6.2.el6.x86_64 ? (fail2ban is 0.8.10 installed) but its slowing down the system completely, i was looking for something which can be similar ...
4
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2answers
127 views

Is there something like one-time sudo?

Is there a way to have a one-time sudo account? My use-case is the following. I have an Ubuntu station with no remote ssh allowed to that machine. The machine generally serves as a public-use ...
2
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0answers
65 views

CUPS and printer security

I would like some help on securing a networked printer. Specifically, I'm interested in the following: 1) Preventing unauthorized access to the printer: I would like only certain laptops that connect ...
2
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0answers
129 views

Writing to Arbitrary Memory Addresses [closed]

I'm reading "Art of Exploitation 2nd Ed." and I have a question regarding a section on format string attacks. Target program Below code (fmt_vuln.c) is a target program. #include <stdio.h> ...
3
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1answer
149 views

present users a login prompt? /bin/login? getty?

I have a service that execs a command when a user connects to it through a socket, and redirects everything it receives to the executed program. It works ok with shells like bash, giving the user a ...
4
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2answers
2k views

rkhunter warn me about root.rules

I run : :~$ sudo rkhunter --checkall --report-warnings-only One of the warnings I've got : Warning: Suspicious file types found in /dev: /dev/.udev/rules.d/root.rules: ASCII text and ...
1
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1answer
178 views

How to recognize harmful AUR packages

How do I recognize if a package which is installed via yaourt on arch linux could be harmful to my pc? I read in the wiki that I should check every installation I make with yourt. But what exactly do ...
2
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1answer
95 views

How 'passwd' gains ROOT user permissions?

How does Linux knows that it has to give euid 0 (uid of root) to only certain process like passwd, setuid, etc. If a process can gain root user's permissions, will it not lead to security breach in ...
0
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2answers
157 views

SSH authentication by public key and password in the same time

Something is not clear to me with SSH authentication. I have a Talend job which connects to sFTP (using SSH protocol) and on the property page of the component, I have the choice between: 1. ...