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

learn more… | top users | synonyms

1
vote
0answers
13 views

Could not load host key: /etc/ssh/ssh_host_ed25519_key in /var/log/auth.log

I have an Ubuntu 14.04 instance running on AWS. I was browsing the auth logs (/var/log/auth.log*), and noticed the following line appearing: Could not load host key: /etc/ssh/ssh_host_ed25519_key ...
0
votes
0answers
17 views

Security concerns while dual booting Windows 8 and Ubuntu

In light of recent intrusive additions to ESEA's client I have completely reformatted my computer and re-installed Windows alongside Ubuntu. Here's my setup: 1 SSD fully dedicated to Windows 8.1 1 ...
0
votes
0answers
40 views

How to encrypt dual-booted Xubuntu?

I'm running a dual-booted Windows and Xubuntu system. I need full partition encryption, but only on the Xubuntu side. Is it possible to set it up without loosing any data? Which method is the safest ...
0
votes
1answer
30 views

ssh key is missing and I've been logged out of all my sites

What conclusion would you draw if you've been logged out of all sites on Firefox and your VPS has been removed from your known_hosts file in .ssh on a personal computer?
3
votes
1answer
37 views

How to show all files created on a specific date

On 16/05/2015 at 17:18 I visited a malicious website. And I suspect a drive-by-download, so I want to check my machine to see since that time in order of creation which files have been created or ...
0
votes
0answers
19 views

Why does dnsmasq use /bin/dash?

I am running apparmor in enforce mode for most profiles, and I regularly see denied messages like the following one: apparmor="DENIED" operation="exec" profile="/usr/sbin/dnsmasq" name="/bin/dash" ...
-1
votes
0answers
24 views

Do not know how to install grsecurity [on hold]

So I verified the grsecurity and kernel I did the first part from this http://en.wikibooks.org/wiki/Grsecurity/Configuring_and_Installing_grsecurity But now i have a folder linux-3.14.42 and i dont ...
1
vote
1answer
32 views

What is this and how can this happen? Is this a security issue or can it be a virus?

From the last 3-4 days, my laptop has started becoming much laggy when I'm working on Android Studio or if it is just running in the background. So, today again I was working in Android Studio. My ...
2
votes
0answers
10 views

How to enable unhide in rkhunter

I have installed rkhunter with: sudo apt-get install rkhunter And even though I have enabled all test, when I run: sudo rkhunter --check --sk If I check in the log file, I see this about the ...
0
votes
0answers
27 views

Upgrade hardware enablement stack but retain kernel

Ubuntu 14.04.01 According to official documentation, upgrading the hardware enablement stack in Ubuntu to utopic-lts upgrades the kernel and xorg. I only want to upgrade xorg to correct a display ...
2
votes
1answer
16 views

Installing Tripwire

I just installed a fresh version of Ubuntu 15 and while I installed it I did not connect to the Internet. I have read you should install tripwire first thing after a fresh install and before you even ...
2
votes
1answer
25 views

Mumblehard Malware on my Server?

this morning, I watched a monthly webinar about IT-Security. One of the actual topics was the malware "mumblehard". This malware makes your server to a part of a botnet and sends spam via email. The ...
1
vote
0answers
19 views

Cannot download security updates in Lubuntu 14.04 LTS

Software Updater offers Security Updates--Ubuntu Base--61.9MB. I click Install now and authenticate. Screen shows "Failed to download package, check your internet connection'. There is no problem with ...
-1
votes
0answers
36 views

This Connection is Untrusted

I am trying to open various websites in Google Chrome, but it says they are all untrusted. To fix this I was adding that particular site on the exception list but when I added it says- "Certificate ...
0
votes
0answers
57 views

Is this a security threat (failed SSH login as root)

I was checking the /var/log/auth.log and I found it's full of these two paragraphs May 6 07:42:12 mypc2 sshd[4489]: Failed password for root from 221.229.166.29 port 36998 ssh2 May 6 07:42:18 ...
3
votes
1answer
42 views

Is running packages from Ubuntu universe more risky than running the same packages on Debian? [on hold]

I am running Ubuntu LTS Server. Are there any concerns with security patching of universe packages? I mean am I in risk of running vulnerable system if having universe packages when compared to the ...
0
votes
0answers
35 views

/var/cache/apt/apt-file/gb.archive.ubuntu.com_ubuntu_dists_vivid-backports_Contents-amd64.gz: PUA.File.Exploit.CVE_2012_1461 FOUND

I recently scanned my machine with ClamAV (using the latest virus definitions) with this command: sudo clamscan -r --detect-pua --infected --bell / And this was one of the outputted results: ...
1
vote
1answer
174 views

.android Folder and adbkey Files

Today I discovered a folder in my home directory with the name ".android". Inside the folder are just two files, "adbkey" and "adbkey.pub". I have searched around and have found out that adbkey.pub ...
0
votes
0answers
6 views

Defining what happens after trying 3 times to add a user with a pass that doesn't match the pass-policy set in pam.d

I've set a password policy, when creating a user for example, so that just passwords with at least 1upper- 1lower-case, 1symbol, 1digit and minimum 10character length are accepted. Now the problem ...
1
vote
1answer
36 views

Set password security with pam.d (urgent homework)

I am trying to change the password security check. I would like to set rules for the password when adding a new user. Here is the content of my /etc/pam.d/common-password file: password ...
1
vote
0answers
15 views

How do I close Chrome when entering standby or hibernate?

If I leave Chrome open, it keeps me logged into my sites even during standby, so the only defence I have is my Linux password. I would like to have Chrome shut down on standby or hibernate, and then ...
3
votes
0answers
49 views

KeePass2 and KeePassX, which is more secure? [closed]

I use KeePass2 on Windows and KeePassX on Linux. I understand the arguments between the two on database compatibility and cross-platform performance. What I'm curious about is whether either one is ...
0
votes
0answers
17 views

How can i Change the Password of hostapd

i am using hostapd wi-fi access_point ,the moment i turn-on the hotspot unknown device are accessing it .Can you tell me the procedure to change password of hostapd?
0
votes
0answers
46 views

Connect button grayed out in 802.1x authentication dialog

Since I upgraded to 15.04 I can't connect to our office wired network anymore since I can't press connect in the authentication dialog.
3
votes
0answers
23 views

Are WINE applications sandboxed? [duplicate]

I want to run a small Windows program that has no reputation. I can always scan it, but I can't get feedback from other users on its performance or if it is at all malicious. Rather than go through ...
0
votes
0answers
14 views

How can I secure Ubuntu while allowing me to login remotely? [duplicate]

I'm very new to Ubuntu and I would like to know how to secure Ubuntu but still allow me to login remotely. Preferrably using ssh keys and how I can and should do it. :)
0
votes
1answer
8 views

Reenable ASLR Ubuntu

For some buffer overflow tests, I disabled ASLR in Ubuntu 14.04 using below command: echo "0" >/proc/sys/kernel/randomize_va_space however trying to enable it agian, my developed program run in ...
0
votes
1answer
14 views

How to install Ubuntu on a small partition with the highest security settings

I want to make a fresh Ubuntu installation on my laptop. In the past I used to follow the default installation instructions by creating a single partition and then enabling passphrase and encrypting ...
0
votes
0answers
26 views

ubuntu 14.04 firefox starting without sudo gives security library failure on SSL sites

I have a problem with ubuntu desktop 14.04. When executing firefox without sudo, then all the https sites (even http://google.com) gives me Error code: sec_error_library_failure But when ...
1
vote
2answers
19 views

How to check validity of an Ubuntu installation via debootstrap?

My goal is to set up an Ubuntu Server installation via debootstrap from another Ubuntu installation and to be sure that this new installation is a correct Ubuntu installation without modifications. ...
0
votes
0answers
26 views

How can I get capabilities to work with su?

I added a line to /etc/security/capability.conf so I can have a user who can read everything for backups, but not do everything root can. cap_dac_read_search backup If I add a password and shell ...
1
vote
2answers
41 views

Is there a way I can password protect a folder without encrypting/compressing?

I have got a folder that contains private stuff and I don't want others to be able to see its content. I will frequently open it and the folder is quite large. I know I can password protect it by ...
2
votes
1answer
13 views

Priority field in CVE pages on http://people.ubuntu.com/~ubuntu-security/cve/CVE-XXXX

On http://people.ubuntu.com/~ubuntu-security/ security patches for packages are announced and correlated with the corresponding CVE from Mitre. I just wonder, how the "Priority" is set. For ...
1
vote
1answer
192 views

Security of Ubuntu flavours, especially Kubuntu

Does Kubuntu gets the same level of OS security as Ubuntu with the Unity desktop? Does Ubuntu developers offer special security updates to the unity desktop, or security is only dependent on the ...
4
votes
1answer
61 views

How do I allow a user to only run the apt-get update command with sudo?

I cannot figure out how to allow a user (in this case test) to only be able to run the apt-get update command with the sudoers file. When ever I try to add the user and then test it out it still does ...
3
votes
2answers
72 views

Are there any security issues with making my /etc/sudoers publicly readable?

I've recently started to use my GitHub account as a way to synchronize my various config files across computers, including my /etc/sudoers. Are there any security vulnerabilities that this exposes? ...
2
votes
1answer
786 views

PUA.Win.Exploit.CVE_2012_0110 FOUND

I recently scanned my system with (I am running the latest version of ClamAV and my definitions are up-to-date): sudo clamscan -r --detect-pua --infected --bell / And this one was of the results: ...
1
vote
0answers
25 views

Upgrade, unable to boot [closed]

I've just done a regular upgrade on my system. I restarted my computer and Ubuntu won't load. All I've got is a small blue window that says HDD has been blocked by the current security ...
2
votes
1answer
24 views

Does Kubuntu have GPG keys?

Does a Kubuntu have a GPG keys to prove the authenticity of OS image? I saw the Ubuntu have, but didn't see anything for [K]ubuntu.
3
votes
0answers
31 views

Find Kali Security tester tools after installation

I'm a 'beginner' with Ubuntu. I tried it already a few times. I also tried Kali, etc already. I think Ubuntu is very useful, and has many possiblities. But I missed one thing from Kali. The Security ...
2
votes
1answer
22 views

Can PGP keys in Ubuntu be replaced?

If some attackers compromised an ISO image of Ubuntu and replaced inner PGP keys , then I will not to able get & install security updates. Is it right? I'm asking it because I possible may meet ...
0
votes
0answers
13 views

DropbBox suddenly restarted with “Killed” message

I have installed DropBox with: cd ~ && wget -O - "https://www.dropbox.com/download?plat=lnx.x86_64" | tar xzf - And it normally works fine, but today when I was syncing with my online ...
1
vote
1answer
24 views

Encrypt second hard disk with same password

I installed Ubuntu 14 LTS with disk encryption (selected during installation). I have two questions: 1- What is encryption algorithm of current encrypted disk? 2- I have a second hard disk and I ...
0
votes
2answers
53 views

Was my SSH server compromised? If so, how, and what steps should I take?

I recently enabled ssh access to my machine to work on a group project with my classmates. I read the guide for setting up ssh on ubuntu and tried to follow good security practices. I disabled ...
2
votes
0answers
25 views

What's up with the sudden appearance of .AppleDouble folders all over my filesystem?

Something I have never seen on my Ubuntu machine before now- .AppleDouble folders have appeared in many different folders all over my filesystem. It creeped me out- like someone on a Mac was looking ...
0
votes
1answer
43 views

UFW blocking connection every minute at home [duplicate]

I'm using a router to connect to the internet at home. I used a long password with WPA2/AES, changed the SSID and changed the default password. But strangely, even if I disconnect the router from the ...
-3
votes
1answer
81 views

need to check if my ubuntu 14.10 has been hacked [closed]

I have a Ubuntu 14.10 machine and I would like to check if my security is OK. I doubt that some one accessed my machine from internet and remotely controlled it. so what are the suitable tools I need ...
0
votes
0answers
26 views

Tiger Warns and Alerts

I am using Plesk 11 and have installed Fail2Ban, RKHaunter and Tiger. Tiger and Fail2Ban sends me emails, but Tiger shows a lot of warnings and alerts. # Checking for known intrusion signs... # ...
0
votes
1answer
59 views

Can an unmounted USB be infected my malware?

Yesterday, I went on a dark creepy site whose js freezed my system/firefox (Ubuntu 14.04 up to date, Firefox 37.0.1 up to date). Now I tried, from the same system, to find any malware with: sudo ...
1
vote
0answers
44 views

Start programming [closed]

I am a beginner ubuntu user, and I am interested in learning a programming language. My demands are that I would like it to help me master the command line, and be a good base voor learning future ...