Security covers a wide-ranging set of topics including Users, Permissions, Authentication, Authorisation, Upgrades, Firewalling, Hardening, etc.

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23 views

shutdown or reboot after entering wrong password x times

My laptop is configured with a bios password to unlock the encrypted ssd. Most times I don't shut it down and use just suspend/resume - this of course leaves the ssd accessible. To increase security ...
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1answer
31 views

Does posting my computer name publicly make my system vulnerable?

I am wondering if it is paranoia and/or privacy overkill to block out one's computer name when posting terminal output in public forums? I don't know enough about networking to know if it's possible ...
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1answer
96 views

Is Ubuntu 16.04's Snap format secure?

A recent leak claims that Ubuntu's new Snap Format is not secure - http://news.softpedia.com/news/developer-claims-that-canonical-s-new-snap-format-isn-t-secure-on-ubuntu-desktop-503287.shtml. Since ...
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43 views

How to trigger lock-screen on visiting a website?

The website in question is my Google Drive. I have many confidential data in my Google Drive. And my google account is signed in on my laptop. Also I tend to leave it unattended at times. I want to ...
4
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1answer
32 views

How can i find that which file was copied from my pendrive last time?

I forget my pendrive in my office. I have doubt that someone copies my important documents and files from my pendrive. Is there any method to find that which file is copied from my pen-drive? Please ...
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1answer
27 views

How to detect screenshots in Ubuntu?

Apart from monitoring keystrokes for Print Screen, is there a way for a tool or software running in Ubuntu (whatever the desktop) to detect that a screenshot or video recording of the whole or a part ...
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1answer
27 views

Secure way of geting checksum

I was just wondering, is there any way of how to securely get checksum from major branches of ubuntu? As a general rule I do not trust anything that can be easily manipulated for that I do not believe ...
2
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1answer
42 views

Is choosing 'Security Updates Only' on installation of Ubuntu Server enough?

I want necessary security updates on my Ubuntu servers, without my interference. In general, do I need to do anything else after selecting the 'Security updates only' option in the automatic updates ...
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3answers
400 views

What does this “find” command do?

I am so beginner on Linux and I have run the following command while I am on /root: find . -type d -exec chmod 770 {} \; && find . -type f -exec chmod 660 {} \ I meant to run that on a ...
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1answer
38 views

Ubuntu Touch - Screen locking fade issue

On my Ubuntu phone, I have set my screen lock to come on after a minute of none use. This is in the Settings > Security & Privacy > Locking & Unlocking. The lock does come on as requested ...
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2answers
21 views

Regular security checks on server [closed]

I am administrating a server and obviously i am slightly paranoid if its security is compromised. Hence i regularly try to check if the security is still intact. Here are the things that i do roughly ...
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0answers
12 views

Evaluating URL Whitelists for Security Threats

I have a very long list of URLs to whitelist on my Ubuntu Squid proxy. I have looked through this list that was provided by another group and there are sites in the list that seem to range from "...
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0answers
18 views

lxcbr0 stop container communication

I'm creating LXC containers to be used by different users but required each container to connect to lxcbr0 to provide remote access. How can I restrict with LXC that containers on a default bridge ...
2
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1answer
523 views

What do I do about Badlock on Ubuntu 14? [duplicate]

So, the Badlock bug (www.badlock.org) that was revealed yesterday, was not as terrible as feared. And yet, it seems prudent to patch samba ASAP. However, just prior to releasing the bug, the samba ...
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2answers
4k views

What is the name of the security concept that explains why Linux asks for root password?

Whenever I'm installing new software or making changes to the system, Linux asks for the root password. What is the name of this security concept and where can I research more information about it?
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2answers
2k views

What is the 'Badlock Bug'?

A user on the Ask Ubuntu General Room posted a link to Badlock. After some googling around, all I can find is that it is a mysterious security bug, that uses the same website template as Heartbleed. ...
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0answers
30 views

Restrict user to run only one program with Wine

I want install Wine and Picasa for an user. I want prevent the user from running *.exe-Files basically for security reasons. In the past (bevor 3-4 years, another Ubuntu-Installation) I discovered, ...
8
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2answers
95 views

Is the lock screen secure?

I have a fully encrypted drive so I know when my laptop is turned off that nobody can access my data but what about when the screen is locked with my root password? It is often impractical to turn ...
0
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1answer
53 views

File/folder protection that even government cannot break [closed]

If I have some intellectual property file that under no circumstances my competition can view, what is the best and most secure way to protect them? I know that there are many encryption apps for ...
3
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1answer
73 views

is the current Adobe Flash 'ransomware vulnerability' affecting Ubuntu users?

Currently there is an important release from Adobe telling users to update their Flash after learning of certain vulnerabilities where users computer are infected with ransomware. One of the many news ...
8
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1answer
341 views

How to prevent users from changing their password to one of the last X passwords?

I have an Ubuntu GNOME 15.10 with GNOME 3.18 system which I would like to set up so that the users using it cannot set a new password as one of the previous X passwords, how can this be achieved? ...
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0answers
25 views

Ubuntu Vulnerabilities Filtered By Severity

It there a page that provides a list of Ubuntu security vulnerabilities by priority? The CVE Tracker seems to be colour coded by priority but I'm looking for something that I can easily filter based ...
0
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1answer
37 views

Permission denied for ubuntu shell user to list home directories of users

When I use shell I can't list the directories of local home users created by useradd or through virtual min ls -ls /home/someuser/ permission denied but I can list directories created by root. ...
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1answer
59 views

Fix duplicate error sudo apt-get update .Help me!

I trying update security ... sudo apt-get update And faiel... Reading package lists ... Done W: Duplicate sources.list http://archive.canonical.com/ubuntu/ precise entry / i386 partner Packages (...
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2answers
159 views

Can someone determine my previous sudo password was if they have access to my machine and my new one?

I have found a bug and the developers to whom I reported this bug to want me to send them the VM with the bug. They want me to send them the password and the VM in its current state (a snapshot). I ...
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0answers
45 views

Is it possible to make HASP4 key working in 14.04 x64?

I'm trying to install HASP4 service on Ubuntu 14.04 and for now I don't know why key is not accessible over network. What I have: root@zentyal:/etc/init.d# /etc/init.d/haspd restart Stopping hasplmd....
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2answers
481 views

Postfix Mail Server. Someone is sending Mails from my server

I am receiving Mails from my own mail server, from a user that belongs to my domain, but is not listed in my mail user db. Here are the logs: 4679 Mar 28 15:54:13 Bumblebee postfix/smtpd[29350]: ...
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1answer
23 views

How to check logs for all connections Linux made to servers and/or downloads

I downloaded Sophos a few days eariler, but now I'm worried I might've got it from a bad source. Is there a way to check to see where I've got it from without using the download list of Chromium (It ...
0
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1answer
22 views

Switching back to an older version having high period of security and maintenance [duplicate]

I am presently using ubuntu 15.10. Just want to know if I can switch back to an older version which has more security and maintenance as 15.10 has only a 9 month one.
3
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1answer
82 views

Do malicious web sites ever exploit vulnerabilities in Linux clients? [closed]

Do malicious web sites ever exploit vulnerabilities in Linux clients? Are there any documented instances of this happening in the wild? I am talking about actually taking over the client's machine ...
21
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3answers
1k views

How do I run a sudo command needing password input in the background?

I have recently disabled sudo's authentication caching ability so that it now prompts me for a password every time. And though this is good for security, it has caused one slight problem which I ...
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0answers
20 views

want to change password on ubuntu entirely in a single line with no prompt

echo somepassword | passwd --stdin someaccount does not work. Why not? I don't care that it appears in the process table for an instant or is recorded by process accounting.
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0answers
75 views

Can an Ubuntu system get infected by a Macro Virus for MS Office / LibreOffice / OpenOffice?

We are running Ubuntu on several office machines, which are used to handle administrative tasks on a daily basis, e.g. to receive applications via e-mail. We now had the situation that we received "...
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0answers
98 views

How to Set-Up WOL with Intel 82574L?

I am setting up a Ubuntu PC which I only need to do Matlab computation efficiently through VPN connection. My network card should be ok (Intel 9301CT where processor Intel 82574L) which Ubuntu ...
0
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2answers
243 views

linux-image-generic vs linux-image-x.x.x-xx-generic security updates

I have an Ubuntu 12.04 32 bit server running with unattended-upgrades set up to only install security upgrades. I have the linux-image-generic and linux-headers-generic packages installed and am ...
1
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1answer
59 views

Preventing from DDOS attack

I think I am under a DDOS attack, I found these lines on my access.log: 41.214.156.122 - - [21/Mar/2016:06:01:40 +0300] "POST / HTTP/1.1" 200 41765 "-" "Dalvik/2.1.0 (Linux; U; Android 5.1.1; SM-...
2
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1answer
27 views

Trying to grasp the linux file permission concept

I know how to change file permissions, ownership etc. But sometimes I feel I don't know what would be the best approach security wise. I just change permissions or ownership to make things work, but I ...
5
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2answers
2k views

How to securely ssh into a machine at home over the internet

I will be travelling shortly, and I have a machine that run runs a bunch of cron jobs etc. I need to log in remotely to check the results of the jobs run and to do some work on the machine. Here are ...
4
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1answer
99 views

How is the guest account prevented from using su and sudo?

It's already known that the guest account can't use su or sudo: Why is su disabled from guest sessions? Sudo not available in guest login How is this done? My guess would be apparmor. However, ...
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3answers
94 views

How to prevent scripts/commands hijacking your session's cached sudo ability?

If I run a sudo command it will ask me for a password, however in that Terminal session for the next few minutes it will allow me to run sudo commands without asking me for a password as it will cache ...
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1answer
33 views

OS on external hard drive

If I put a OS like Ubuntu onto a external hard drive, would it allow viruses to infect my internal hard drive? If more info is needed, then feel free to ask.
0
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3answers
2k views

Are there any good antivirus for Kubuntu/Ubuntu as of 2015? [closed]

OK, I do have to admit I am somewhat new to Linux,(I'm used to Windows), and that's why I'm asking all of these questions about Kubuntu. As of 2015, are there any good, FREE anti-virus programs for ...
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0answers
49 views

Ubuntu chrome, and firefox with untrusted certification authorities

I have this as some of my server certificates, also some authorities. At least three users I know have this. Is this a bug? What should I do? dpkg -l ca-certificates Desired=Unknown/Install/Remove/...
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0answers
12 views

Is ClipIt safe? How would I test this? [duplicate]

I have seen that Clipit has an "Offline mode", which is described in this question. However, it shocked me as I thought that perhaps it was storing my data online, which would be a security concern. ...
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1answer
48 views

using VNC with SSH securely

While I know there is a plethora of available information on how to set up VNC for remote desktop viewing, some of which outlines the importance of using SSH to ensure security, I want to know dome ...
1
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1answer
65 views

How does ubuntu ensure software security bfrom external developers [duplicate]

I was reading on the hack against the Transmission Bittorrent Client. http://arstechnica.com/security/2016/03/first-mac-targeting-ransomware-hits-transmission-users-researchers-say/ It got me ...
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0answers
23 views

Make last command shows also sftp sessions

last command searches back through the file /var/log/wtmp (or the file designated by the -f flag) and displays a list of all users logged in (and out) since that file was created. On my Ubuntu ...
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2answers
153 views

LXD,LXC containers security

I just want to know dose the Linux containers (LXD) provide security? Such that if on container get infected with a virus will that effect the entire system (kernel+other containers) Or it will ...
1
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0answers
48 views

Is “oneconf-service” meant to be running?

I left my computer for a little while, and when I came back it told me that there was an internal error with oneconf-service, and though it (the process) is gone now, in the processes list in the ...
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0answers
77 views

When was SSLv2 disabled from OpenSSL in ubuntu 14.04 LTS?

I tried to find out without success when (in which package version) SSLv2 was disabled from OpenSSL in Ubuntu 14.04 LTS Trusty Tahr? Could anyone help me with this?