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

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What does the Heartbleed bug mean for Ubuntu? Is Ubuntu not as secure as I thought? [duplicate]

I hope this question isn't closed for being subjective because I think there is a correct answer somewhere, even if it's a wiki-style explanation answer. One reason for using open source software for ...
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39 views

SELlinux security domains

I am studying SELinux, but I can't find any clear definition for security domains. What is a security domain and what is its difference with security context?
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1answer
158 views

Ubuntu security: “antivirus” in official statement?

I use current (and vanilla) Ubuntu in a work environment. (It is, in the main, a Windows-orientated outfit.) A question has come up about antivirus, and I see this on the official Ubuntu website: ...
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0answers
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How to auto restart services when you get security updates?

That's related to the heartbleed bug. While my server (12.04 LTS) was configured to perform unattended install of all security updates, it seems that nginx was not restarted so it was still affected ...
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2answers
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Patch OpenSSL CVE-2014-0160 on ubuntu 12.04?

NO, this is not a duplicate of How to patch the Heartbleed bug (CVE-2014-0160) in OpenSSL?. So, read on. I am seeing conflicting information with respect to Ubuntu 12.04: The Heartbleed page claims ...
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1answer
2k views

Problem updating OpenSSL in 13.10 - How to diagnose or work around?

Following the instructions in the existing question on the OpenSSL bugs, I've run apt-get update and upgrade, and rebooted. Now when I check the version, I do not have the version mentioned in the ...
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1answer
53 views

Are pre-releases not getting security updates? [closed]

I got a new computer a couple of weeks before the expected Trusty release date, so to save my the trouble of first installing Precise and then upgrading, I installed Trusty Final Beta. Now I see that ...
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2answers
3k views

12.04.4 server can't verify common SSL certificates, usual fixes failing

The Problem I've got one server in a farm which is suddenly unable to correctly handle SSL certificates. Attempting to do a curl command like curl -v https://google.com results in: curl -v ...
137
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6answers
106k views

How to patch the Heartbleed bug (CVE-2014-0160) in OpenSSL?

As of today, a bug in OpenSSL has been found affecting versions 1.0.1 through 1.0.1f (inclusive) and 1.0.2-beta. Since Ubuntu 12.04, we are all vulnerable to this bug. In order to patch this ...
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199 views

Security Antivirus [duplicate]

brand new to ubuntu...I know there is way less virus problems then windows, however, is the security within the OS enough or do you suggest Antivirus program also (this is assuming the individual is ...
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1answer
8k views

Fingerprint reader driver for Validity Sensors Fingerprint scanner

prakhar@pr3d4tOr:~$ lsusb -s 001:003 -v Bus 001 Device 003: ID 138a:0018 Validity Sensors, Inc. Fingerprint scanner Couldn't open device, some information will be missing Device Descriptor: bLength ...
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1answer
363 views

Ubuntu 12.04.4 x64 - How to disable SSH daemon

I've read in this thread that running the SSH daemon with root privileges enabled by default is a potential path for malware infections: How to deal with malware on my laptop? How can I check ...
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1answer
66 views

Security benefits to force users to change their password at first login

When I consider chage command, I found that I can force users to change their password at first login with following command: $ sudo chage -d 0 <user-account> Has this work any security ...
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24 views

New user only RWX one directory

So, I read this: Is it possible to create users that can only use one directory? I would like to make it where my newly created user "kevin" (to keep in theme with the referenced post) cannot RWX in ...
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2answers
69 views

Reusing old passwords

pam_cracklib module is capable of consulting a user's password "history" and not allowing them to reuse old passwords. What security risk is in reusing old passwords? If this work is useful, how many ...
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2answers
75 views

unnecessary accounts in ubuntu

It is recommended in hardening process that remove unnecessary accounts. What security problem exist with unnecessary user account? Are there recommended user accounts that should be removed?
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1answer
670 views

How to deal with malware on my laptop?

I am fairly certain that my Ubuntu 13.10 laptop is infected with some sort of malware. Every once in a while, I find a process /lib/sshd (owned by root) running and consuming lots of cpu. It is not ...
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45 views

full disk asymmetric encryption

Wondering if there's a protocol and open source program for full-disk, asymmetric encryption. Something like, encrypting the keys into the start of the disk (using AES/something stronger) and then ...
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1answer
629 views

Is having Lubuntu 12.04 a security risk?

I have a computer with Lubuntu 12.04 installed. Since unlike Ubuntu 12.04 Lubuntu is not LTS, I will not get Lubuntu updates. However, I am still getting updates (I guess these are the general Ubuntu ...
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1answer
89 views

Encrypted Lock Screens?

I really like the disk encryption to secure my funds, but my problem is I practically never have my computer off. I live a very busy life and shutting it down totally every night is entirely ...
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What auditing information is available for Universe repository software packages?

I understand that the "Masters of the Universe" (MOTUs) are responsible for packaging and reviewing/checking software that goes into the Universe repository, but there seems to be no formal process ...
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1answer
4k views

linux command to prevent dos attack by using netstat and iptables

I want to DROP more than 200 requests per ip to prevent ddos attack. this is command that i used to detect requests count per ip : netstat -alpn | grep :80 | awk '{print $5}' |awk -F: '{print ...
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3answers
449 views

Should Ubuntu users be concerned about “Operation Windigo”?

Should desktop users of Ubuntu (and other Linux distros) be concerned about the malware-infection drive described as "Operation Windigo"? What threat does it pose to us immediately and are there any ...
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1answer
85 views

How to launch program on lock and close it on unlock [duplicate]

Have siblings who like to "play" with my laptop by waking it from suspension and then typing random keys on the keyboard into the password field. Afterwards, they always deny it. I plan to install ...
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0answers
113 views

Why has Ubuntu One Music Store not renewed its security certificate? [closed]

I have been trying to download music from the Music Store but Firefox tells me the security certificate expired two days ago so it won't let me. Is this something they might not realise, i.e., do ...
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1answer
215 views

What are the possible threats if internal IP address is publicly revealed?

In many cases, people do not take enough care to remove their IP addresses from some output before posting it to help forums and Q&A sites like askubuntu. Considering one's IP address is revealed ...
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1answer
217 views

How To Install Djigzo on Ubuntu?

Can any one provide step by step configuration to install Djigzo? Djigzo Website.
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1answer
162 views

Disable logon prompt show hostname

Per default the login prompt shows %hostname% login:. I don't want anybody with console access to see the hostname of the server that easily. How to get rid of the hostname there?
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1answer
355 views

Prevent www-data from running scripts and programs

I discovered this little PHP script that allows you to enter GET requests manually from the browser address bar and execute commands. I played around with it and discovered that I could do all kinds ...
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0answers
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Hide “Places” or “Username” in File Chooser Dialog

Background Making a video-capture of a website demo; part of the demo requires uploading files. Problem The username is displayed in the video, which is a security concern. Question How do you ...
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1answer
58 views

how to encapsulate HTTP in a HTTPS session

Team, hi, I'm looking for a solution that would allow me encapsulate incoming HTTP traffic, with HTTPS traffic from my application (HTTP in an iFrame), and deliver both as HTTPS. Can Squid proxy do ...
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5answers
10k views

Package denyhosts in Ubuntu Trusty Tahr is deleted: temporary or forever?

While doing a test-upgrade of our Ubuntu server to 14.04, I found that the package DenyHosts is no longer available. Installing it gives following error: apt-get install denyhosts Reading package ...
5
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1answer
210 views

Rootkit on port 60001 !? Tiger says so - how do I verify? [closed]

My system is an up-to-date Ubuntu 13.10 I've installed Tiger and I'm getting this # Running chkrootkit (/usr/sbin/chkrootkit) to perform further checks... OLD: --ALERT-- [rootkit005a] Chkrootkit has ...
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1answer
915 views

Do modifications to sysctl.conf take effect in openVZ container?

I'm following a security guide(http://www.thefanclub.co.za/how-to/how-secure-ubuntu-1204-lts-server-part-1-basics) to strengthen my OpenVZ based VPS webserver running Ubuntu 12.04 , a part of that ...
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1answer
82 views

gksudo from a non sudoer?

I want to run gui applications that require admin privileges from gksudo/gksu on a non-sudoer account. Currently, I can just run sudo guiapplication from a sudoer tty, and will be able to display/use ...
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1answer
2k views

Is there a NSA backdoor in ubuntu desktop os? [closed]

I heard talk of selinux being in ubuntu and it being a nsa backdoor. Source of my worrying :( So are these guys right? Is there a backdoor in Ubuntu (I use xubuntu if that matters)? Have any of you ...
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122 views

Analyze firewall logs to track intrusion

I have just started this topic where the firewall on my router detects intrusions e.g. Mar 11 14:15:11 kernel warning kernel: [fwlog] Intrusion -> SRC=85.102.133.241 DST=109.78.126.234 ...
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3answers
114 views

Encrypted files on a server [closed]

There is a way of encrypting the data files stored on the server to harden them against direct access or hacking. The website is in /var/www as usual and uses PHP to access data on another drive ...
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2answers
115 views

How to prevent users from deleting files that are already in use?

Consider this scenario: User is executing a command on a file. This file becomes 'in-use' now. $ tail -f somefile.log In another shell, user deletes the file. $ rm somefile.log Now, this file ...
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1answer
61 views

Are any Ubuntu (Linux) vulnerabilities in media applications?

Ubuntu (Linux) has a solid system that permits and requires root privileges to modify the system. However; if an installed application eg. VLC, audacious, some image viewer installed from the ...
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1answer
74 views

ubuntu 13.10 - not prompted for login at start up

Mostly - oddly not every time - when I reboot, or start up my laptop, I am not prompted for a password; it goes straight into my desktop. I don't like this one bit. There are other users on my laptop, ...
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3answers
2k views

What is the “Free software only” option when installing Ubuntu?

When installing Ubuntu, you get a Free software only option. Does that Free software only option mean Free as in beer or Free as in freedom? When I say free as in freedom, I mean FSF type of ...
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2answers
57 views

Is the latest provided php5 package in an LTS distribution secure?

I need to update php5 on a 12.04 LTS production server. The latest candidate provided is 5.3.10-1ubuntu3.9. Is that version patched to be secure for use in a production environment? PHP is up to ...
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1answer
39 views

how to limit resources to a shared ubuntu 10.04

The title might not be explanatory enough but I couldn't find any better way to formulate it. I will be running a server for office use. It will host applications on tomcat. 2 differents people would ...
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1answer
1k views

Man in the Middle Attack warning with OpenVPN

When using openvpn --config /home/xxx/vpnbook-uk1-udp25000.ovpn I always get this warning: Sat Feb 22 11:16:04 2014 WARNING: No server certificate verification method has been enabled. See ...
6
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1answer
561 views

What are the risks of running Nautilus as root?

Whenever I try to access files outside my home directory I get a permission error. People keep recommending running Nautilus as root by running the following commands in a terminal: sudo -i nautilus ...
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1answer
222 views

mysterious files and possible virus on ubuntu 12.04.2 server

IT services at my institution discovered our server sending out SPAM emails and flagged it as compromised. Further investigations suggest that it is indeed infected with a virus. For instance, there ...
5
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1answer
7k views

How to secure postfix on Ubuntu Server

I am setting up a new VPS server with LEMP. The only piece missing now is the mail server. Do I need to do something special to make it secure? or it is already secured when the installation is ...
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5answers
3k views

Rename /etc/passwd and /etc/shadow for security reasons [closed]

I have a server. My server is secure, but let's imagine a good hacker that enter in. He can now look into /etc/passwd and /etc/shadow. I would like to rename that files /etc/passwd to something like ...
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2answers
12k views

How can I scan for possible viruses on my Ubuntu system? [duplicate]

I think I may have a virus. How would I go about checking for a virus and how can I protect my computer from any other virus? Please give detailed answer as I'm still learning about Ubuntu.