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0

I am basing much of this on the original post (except for the title). I think my PC is being hacked. What should I do? ... How should I proceed? The first thing you should do is remain calm verify that this is the case. Constructively: Many of the comments in your original post indicate a fundamental lack of understanding of how many of the concepts ...


0

12.04 is supported till April 2017, so I also will be using it on my old PCs till then for its 2d desktop. Will probably go Lubuntu then.


2

If you think you're being hacked personally, below you can find a few very stringent rules to make hacker's lives extremely difficult. Remain calm Turn off all hardware you don't need to be a developer in the BIOS (his includes: microphone&speakers as they have been shown in the past to be used as communication channels once the PC was hacked, printer ...


0

If you're using Ubuntu 12.04, you are still in support, see: https://insights.ubuntu.com/2011/10/21/ubuntu-12-04-to-feature-extended-support-period-for-desktop-users/ However, if you are using a variant such as Lubuntu, you will no longer be receiving security updates so ought to consider an upgrade. Of course, no-one will stop you using an out of support ...


0

Short of entirely encrypting your root partition (with a separate boot partition obviously) there's very little you could do to prevent an attack by someone who has physical access to your system. Physical access==root access.


1

If the attacker has physical access to system, which they need to change the kernel parameters, it's a lost cause without encryption. However, I guess you can limit that particular method (init=/arbitrary/command), by commenting out these lines in the kernel source, and compiling your own kernel: if (execute_command) { ret = ...


0

You do that by using common business practices: Read the Ubuntu Security notices Keep system back-ups of your system (you're definitely user type 4) Have a test system (virtual or not) to test updates before rolling them out Use secure passwords and don't re-use them. Install software intelligently and keep it updated as well. etc...


2

You need to track down each program that is running on those ports. Are you running xmpp yourself? Are you running a webbrowser? Specifically what is connecting to port 40016 and 12350? lsof -i TCP:40016 lsof -i TCP:12350 lsof -i TCP:xmpp-client you might need to sudo those.


1

For instance, cronjobs. They need a shell to run. See Post of Unix and Linux Why does the 'bin' user need a login shell?


2

I don't know if there's a one-to-one correspondence, but you can use the Ubuntu CVE trackers, maintained by the Ubuntu Security team. For example, the tracker for software in main is http://people.canonical.com/~ubuntu-security/cve/main.html:


1

I don't think it's your fault. Version 2.8.98-0ubuntu2 (present in Ubuntu 14.10) of apparmor-utils seems to be buggy. aa-genprof crashes regularly (python errors) and I noticed a similar behavior as described by you with aa-logprof. It fills up some of the rules but others seem to be left out. Hopefully next version will be better. Newer versions are ...


2

You could try to start here. Example how to start There is line of code: #define X86_FEATURE_NX ( 1*32+20) /* Execute Disable */ I already has cloned git repo of linux kernel, it was cloned when the last commit in master branch was 14186fea0cb06bc43181ce239efe0df6f1af260a. So something may be changed right now. Trying to find all files that use ...


0

Firstly, to quote the man page: "unattended-upgrade - automatic installation of security (and other) upgrades" and other - it's going to do the lot... The difference is that security upgrades are deemed important for security - so things like vulnerabilities in programs - & the others are just upgrades to a program with no bearing on security. The ...


2

The security updates are updates that fixes security bugs that can compromise the system, the rest are updates of improvement that fixes non-critic bugs or adds new features to a program. However, its recommended to install all updates. When do you see this: 35 packages can be updated. 22 updates are security updates. Yes, you think correctly, there is a ...


2

Type the following command: gedit ~/.Skype/YourUserName/config.xml Search for <Account> and add in that section: <PrivateSkypeMode>1</PrivateSkypeMode>


1

It's a genuinely interesting idea but not without issues. You could add a "semiadmin" group (your choice on the name), put a user in that group instead of the "sudo" group, and then add /etc/sudoers lines using wildcards to match the common places root-owned commands live: %semiadmin (ALL)=/usr/bin/*,/bin/*,/sbin/* The problem with this approach is you ...


-1

Login as the owner of the file who is not root and revoke execution permission from other users using this command chmod o-x filename


2

Is it bad to have at all times (one) terminal logged in as root? If so, why? I can only say that I worked the same way as you, until I made a huge mistake... most of the time I forgot to add sudo in front of my commands to get the privilege for systemuser. Then on one day I executed as root the command rm -rf / var/www/filenotneeded.html ... as you ...


3

Is it bad to have at all times (one) terminal logged in as root? If so, why? Yes. Well. The idea of logging out your root terminal is due to the fact that Linux is a multi-user system. So other users could walk to your terminal and issue commands you do not want them to issue. With the introduction of desktops (that are often single user) this is less ...


0

Pretty unclear question. You can see if a PC is in promiscuous mode on a LAN, go here: http://security.stackexchange.com/questions/3630/how-to-find-out-that-a-nic-is-in-promiscuous-mode-on-a-lan If you're trying to get in promiscuous mode using python on Linux try this: ...


0

You are seeing a bluetooth connection, which you can get more information on with nmcli: nmcli -p con


1

This is an old question but the only thing I have found while trying to solve a similar issue on my 14.04.2 install. I had a similar menu entry that mysteriously appeared and eventually realised it had appeared after I had paired my phone to my laptop via bluetooth (it would appear whether bluetooth was switched on or not). In my case this seemed to be ...


0

You can accomplish that without any external tools, simply by setting kernel variables. Assuming that you are using IPV4 addresses, to disable ping responses: sudo echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all To reenable ping responses: sudo echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all To disable icmp responses permanently, add this line ...


0

Q1 Ubuntu 14.04 LTS (Trusty Tahr) Ubuntu 14.10 (Utopic Unicorn) Q2 No Open Ports Password hashing SYN cookies Configurable Firewall


1

Editions: See Ubuntu editions. Security Features: See Ubuntu security features.


3

With IPv6 privacy extensions, you don't magically get an address starting with 2001::. Instead, the starting of the IPv6 address will be the what you get from your ISP. You'll still use the prefix of the IPv6 address that's been assigned to you. However, the suffix (the 2nd part) will be randomly generated, instead of being based on your MAC address. If ...


0

I usually use the following permissions under /var/www/virtualhost: chown -R www-data:www-data * chmod -R 640 * This ensures that only the HTTP server can see the files. No execute permission is needed for .js and .php files. Shell scripts (.sh files) probably need them if you want to run them as CGI scripts (I've never tried it, so I don't know how to ...


9

Long ago, I was in a university computer lab where we had... interesting wiring. Apparently, the signal in thicknet is the same as the signal in thinnet and some engineering student had created what looked like a terminator for thicknet and thinnet smashed together... a barrel connector with 10b5 on one side and 10b2 on the other. This was obviously not ...


3

Except for docky, it's just a bunch of data (xml and png), so for a certain definition of "safe" (if you already have installed PPAs) then, yes, it's safe... Now, before you go ahead, please note that one of the few vectors for getting malware onto your computer is a PPA, so never install a PPA because someone tells you so (including me). Always use your ...


7

You can watch the dots from across the room while wiggling the cables to find the faulty connection.


1

I've used ping -f in the past to see if my lines are dropping packets at higher rates and to see if router error counters are increasing. According to the man page only a 0 rate ( which is as fast as it can go ) can be executed by a super-user. I agree with others that ping -f is not a great tool to use for this purpose. Netperf, iperf or other bandwidth ...


0

You can definitely use it for stress testing your own machine as others have said, however at the place I'm interning at the IT professional usually uses it when rebooting a machine remotely, when the machine is back online he will know because it will start responding to the requests.


16

In addition to the other answers listed here about confirming how well hardened a host is, I have used the ping -f as a poor man's bandwidth testing tool for very narrow links. More comprehensive tools like Fluke and Iperf require a cooperating agent at both ends of your link, but if you wish to test bandwidth to a point on your network that cannot easily ...


21

That's obviously ;-) to test whether your system hardening has worked out and that your TCP/IP stack will not be flooded by ping flooding any more... E.g. that your system won't keel over by dropping the enormous amount of ICMP packets that it receives.


15

This can be used to check if the network is reliable or if it is overloaded. The usual one ICMP message per seconds would be too slow for such purposes. Please note that 100 ICMP packets per seconds is very far from being a DOS attack in today's networks. That is only about 150 KB/s even if you specifically send unusually large ping messages.


0

It is recommend that one uses only official repositories of canonical and Ubuntu but still to enhance features of Ubuntu sometimes unofficial repos are required. ppa from noobslab are safe although no one can ensure it but people have been using them from many years and I didn't saw any person complaining about infection from unofficial ppa . Anyway if ...


3

The only way to ensure that a PPA is "safe": Download the source packages published in that repository and check the source code contained in these source packages. Also, before installing updates on your machine, you would have to re-check the PPA to see if a new source package has been uploaded and audit that new source code. Obviously, most users are ...


0

sudo apt-get dist-upgrade done. fixed.


0

The "fix" for courier disables tls 1.1 and tls 1.2. There does not appear to be a way to run courier with tls 1.1 or higher. A PCI scan on your server may come back with the recommendation: Configure SSL/TLS servers to only use TLS 1.1 or TLS 1.2 if supported. Configure SSL/TLS servers to only support cipher suites that do not use block ciphers.


5

From usn-2497-1 it is stated you need to upgrade to ntp 1:4.2.6.p5+dfsg-3ubuntu2.14.04.2. To me that is the same as your 4.2.6p5 though yours is shortend. Update instructions The problem can be corrected by updating your system to the following package version: Ubuntu 14.10: ntp 1:4.2.6.p5+dfsg-3ubuntu2.14.10.2 Ubuntu 14.04 LTS: ntp ...



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